Le droit sur l'admissibilité d'une preuve par expérimentation / L'opinion désigne une « inférence tirée d'un fait observé »

R. v. Collins, 2001 CanLII 24124 (ON CA)

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[16]         Despite the fact that experiment evidence is often, and at times routinely, admitted at trials, there is a paucity of Canadian jurisprudence relating to this kind of evidence. Perhaps this is explained by the fact that experiment evidence often goes unrecognized for what it is: in some cases, it consists of mere factual evidence, much like any other sworn testimony; in other cases, it is a combination of factual and opinion evidence. In either situation, its admissibility is governed by well-established rules of evidence.  Indeed, in my view, the key to determining the admissibility of experiment evidence is to keep in mind this distinction between fact and opinion as it is understood in the law of evidence. I will briefly review the applicable principles of law.

[17]         In the law of evidence, an opinion means an “inference from observed fact”: see R. v. Abbey (1982), 1982 CanLII 25 (SCC), 68 C.C.C. (2d) 394 at 409. As stated in Abbey, as a general rule, witnesses testify only as to observed facts and it is then up to the trier of fact to draw inferences from those facts. A lay witness will be permitted to give an opinion only with respect to matters that do not require special knowledge and in circumstances where it is virtually impossible to separate the facts from the inferences based on those facts. A witness testifying that “a person was drunk” is a common example of an opinion that can be provided by a lay witness. See R. v. Graat (1982), 1982 CanLII 33 (SCC), 2 C.C.C. (3d) 365 (S.C.C.) for a review of the law on non-expert opinion. Otherwise, opinion evidence will only be received with respect to matters calling for special knowledge beyond that of the trier of fact. In those cases, an expert in the field may be permitted to provide the judge and jury with an opinion, that is “a ready-made inference which the judge and jury, due to the technical nature of the facts, are unable to formulate” (Abbey at 409). The law as to expert opinion evidence was authoritatively restated in Mohan, supra. Before expert opinion evidence can be admitted, the evidence: (a) must be relevant to an issue in the case; (b) it must be necessary to assist the trier of fact; (c) it must not be subject to any other exclusionary rule; and (d) it must be given by a properly qualified expert.  

[18]         A witness’ testimony as to observed facts is, of course, subject to the general principles governing the admissibility of any evidence: relevance and materiality. Relevance is established at law if, as a matter of logic and experience, the evidence tends to prove the proposition for which it is advanced. The evidence is material if it is directed at a matter in issue in the case. [1] Hence, evidence that is relevant to an issue in the case will generally be admitted. Indeed, it is a fundamental principle of our law of evidence that any information that has any tendency to prove a fact in issue should be admitted in evidence unless its exclusion is justified on some other grounds: see R. v. Corbett, 1988 CanLII 80 (SCC), [1988] 1 S.C.R. 670 at 715; Morris v. R., 1983 CanLII 28 (SCC), [1983] 2 S.C.R. 190 at 201; and R. v. Seaboyer, 1991 CanLII 76 (SCC), [1991] 2 S.C.R. 577 at 609.

[19]         The grounds that justify the exclusion of evidence that is otherwise relevant and material form the basis of many of our more specific rules of evidence. The rule against hearsay, the opinion rule and the similar fact rule are a few examples. Quite apart from these specific rules, evidence that is otherwise relevant and material may also be excluded by the exercise of the trial judge’s general power to safeguard the fairness of the proceedings. Our law of evidence recognizes the general power of a judge to exclude relevant and material evidence where its probative value is outweighed by the prejudice caused by its admission, provided that where the evidence is tendered by the defence, it should not be excluded on that basis unless the prejudice substantially outweighs the value of the evidence: see Seaboyer, supra, at 390; and R. v. S.C.B. (1997), 1997 CanLII 6319 (ON CA), 119 C.C.C. (3d) 530 at 541 (Ont. C.A.). Prejudice in this context does not mean, of course, that the evidence will be detrimental to the other party’s position. Rather, it is related to the detrimental effect that the evidence may have on the fairness and the integrity of the proceedings. For example, the evidence may not be worth receiving if its reliability is clearly outweighed by its potential to mislead or confuse the trier of fact. The evidence could also be excluded where its admission would involve an inordinate amount of time that is not commensurate with its value. See Mohan, supra, at 411.

[20]         These general principles apply to experiment evidence. A pre-trial experiment can be as simple as driving from one location to another to determine the time it takes to cover the distance in order to substantiate or disprove an alibi, or driving along a particular stretch of road to determine at what point a stop sign becomes visible. The evidence in such cases, provided that it is relevant to an issue in the case, will usually be admitted without argument. It is entirely factual, and its admissibility is only subject to the general principles of relevance, materiality and discretion as discussed earlier. In other cases, the pre-trial experiment may be more complex, requiring particular technical or scientific knowledge to perform, and it may also form the basis of expert opinion evidence in the interpretation of the results. In such cases, the experiment evidence, in so far as the observed facts are concerned, will be subject to the usual principles of relevance, materiality and discretion but, in addition, to the extent that it includes inferences from observed facts, the opinion rule will come into play. In order to be admissible, that part of the experiment evidence that constitutes opinion evidence will have to meet the criteria in Mohan.

[21]         In a nutshell, experiment evidence, if it is relevant to an issue in the case, should generally be admitted, subject to the trial judge’s residuary discretion to exclude the evidence where the prejudice that would flow from its admission clearly outweighs its value. Beyond this, when the evidence requires the making of inferences from observed facts that require special knowledge, the test in Mohan will have to be met before the evidence can be admitted as expert opinion evidence.

[22]         In most cases, the relevance of the experiment evidence will depend on the degree of similarity between the replication and the original event. Consider the example given earlier where the experiment consists of the driving along a particular stretch of road to determine at what point a stop sign becomes visible. If the distance at which the stop sign becomes visible is in issue at trial, the experiment evidence will be material, but will only be relevant if the replication bears some similarity to the original event. For example, if the original event occurred in the summer when vegetation partly obstructed the driver’s view but the experiment was conducted in winter after all the leaves had fallen, the relevance of the evidence will be greatly diminished. Depending on all the circumstances, it may not be worth receiving. Similarly, if the experiment evidence includes expert opinion evidence, variances between the replication and the original event, depending on their degree and importance, will affect the weight that can be given to the expert opinion evidence.

[23]         As indicated earlier, there is a paucity of Canadian jurisprudence dealing specifically with experiment evidence. The admissibility of this kind of evidence, however, has been discussed in some cases, and the issue has generally been disposed of without much analysis but in a manner consonant with the principles that I have set out. I will briefly review some of the more relevant cases.

[24]         In Kirkpatrick et al. v. Lament (1965), 1965 CanLII 631 (SCC), 51 D.L.R. (2d) 699 (S.C.C.), the plaintiff brought an action against defendant police officers for damages in respect of brain injuries that he suffered as a result of extensive force used by the officers in making an arrest.  In support of his case, the plaintiff called a witness who testified as to hearing a ‘thud’ from over 100 feet away during the timeframe of the arrest. To contradict this witness, the defendants introduced evidence of an audibility experiment in which a hammer was pounded on the police station floor.  The plaintiff objected to this evidence. On appeal to the Supreme Court of Canada, the Court held that the evidence was irrelevant to the issues at trial, but made the following brief comment about experiments in general at p. 709:

There is much, of course, to be said against that kind of evidence.  It is absolutely impossible to duplicate all the elements affecting audibility on the night in question.  But it would seem that that objection goes more to the weight of the evidence than to the admissibility….

[25]         In  R. v. Laverty (No. 2) (1979), 1979 CanLII 3010 (ON CA), 47 C.C.C. (2d) 60 (Ont. C.A.), the accused was convicted of arson.  At trial, the Crown had relied on the evidence of a fire marshal who theorized that the fire had been started by the partial filling of a bathtub with flammable fluid and then igniting it. To test this theory, he had conducted a simulation in another bathtub, and then examined the blisters. He gave evidence of this simulation and its results before the jury. On appeal, the accused argued that such evidence should not have been admitted. In rejecting this ground of appeal, Zuber J.A. (at 62) relied on the following excerpt from McCormick’s Handbook of the Law of Evidence, 2^nd ed. (1972), c. 20 at pp. 484-485:

Testing the truth of hypotheses by the use of controlled experiments is one of the key techniques of modern scientific method.  The courts in their task of investigating facts make extensive use of this technique, but under conditions which prevent them from exploiting the process to the full limits of its usefulness.  The legal doctrines relating to experimental evidence are simple and the principal task of the lawyer is to recognize the opportunities for their use, to seize these opportunities boldly, and when experiments are employed to plan them inventively and correctly, so that the results derived will be convincing to judge and jury.  We are dealing here with experiments carried out before trial and presented at the trial through descriptions given by witnesses of the experiment and its results…

The opportunities are of limitless variety.  Some of the types of experiments most frequently encountered are these: tests of the composition and properties of substances; testing firearms to show the patterns of powder and shot made upon the object at different distances; experiments by human beings in the holding of firearms to determine whether a given gunshot wound could have been self-inflicted; tests of the visibility of objects or persons at a given distance; tests of audibility and tests of the speed of locomotives and motor vehicles and of the effectiveness of their brakes and headlights.

[26]         Zuber J.A. concluded that the test performed in the case under appeal was “well within the class of cases referred to in McCormick and well within the class of tests which have been customarily admitted in [Ontario courts]”. 

[27]         In R. v. Kelly, [1985] O.J. No. 237 (C.A.), the accused was convicted of first degree murder. At trial, the Crown relied on experiment evidence to contradict the appellant’s allegation that his wife had fallen from the balcony.  On appeal, the accused argued that the experiment evidence was inadmissible, due to “incomplete information and inaccurate assumptions”.  In rejecting this argument, MacKinnon A.C.J.O. stated at p. 2 (QL):

…the information used was substantially that given by the appellant and the tests were conducted in accordance with scientific methodology.  There was no need for a deep knowledge of the laws of physics to question the statements of the accused that he saw his wife falling as he was running from the kitchen and still had time to cross the living-dining room and the balcony and catch her, only to have her slip from his grasp.  However, it was within the jury’s province to weigh the evidence of the tests conducted and introduced by the Crown; the argument that the tests were based on incomplete information goes to its weight and not its admissibility.

[28]         In R. v. Brooks (1998), 1998 CanLII 5686 (ON CA), 129 C.C.C. (3d) 227 (Ont. C.A.), an issue arose as to the cause of a red mark on a young victim of a homicide. It was the Crown’s theory at trial that the red mark was caused by a cigarette burn inflicted by the accused. It was the defence theory that the mark was caused when the victim fell on a red toy funnel in the bathtub. To disprove the accused’s allegation, the investigating officer performed a “crude experiment” with a funnel in his bathtub to determine how it would land in the water.  At trial, the officer testified about the results of this experiment without objection. However, the admissibility of his evidence was contested on appeal. Laskin J.A., in writing for the court, stated as follows:

I agree that the results of Detective Sergeant Harild’s experiment should not have been admitted.  He did not have the required scientific training to give this evidence and the evidence itself was of dubious relevance.  See R. v. Mohan (1994), 1994 CanLII 80 (SCC), 89 C.C.C. (3d) 402 (S.C.C.). But the error was harmless for two reasons. First, the trial judge instructed the jury to ignore the evidence. … Second, the medical evidence at trial showed that the mark was likely caused by a cigarette burn. Indeed the medical evidence dismissed the possibility of a funnel having caused or aggravated the lesion. I would not give effect to this ground of appeal.

[29]         A review of the transcript in Brooks reveals that the police officer’s testimony went beyond relating observed facts and included opinion evidence that would be subject to the criteria in Mohan as stated by the court. The police officer testified as follows:

 What I did was, in light of the evidence where the injury had supposedly been sustained, seeing that this was the aggravating factor that could have caused the injury, what I did was I filled my tub up with different levels of water.  When there was two inches of water in the tub, I would just randomly throw this toy in, flipping it and also that there was no, no consistency in the way it was introduced into the water, and out of the 25 times that I threw it, 24 times it landed like this with the funnel up, because basically this part of the funnel is so heavy that it’s sitting on the water and physics dictates that the heaviest then will end up on the bottom. [Emphasis added.]

[30]         In R. v. Gillese (1993), 1993 CanLII 898 (BC CA), 27 B.C.A.C. 69 (C.A.), the appellant successfully adduced  experiment evidence by way of fresh evidence on his appeal from his second degree murder conviction. The appellant maintained at trial that he had shot away from the victim not intending to kill him. The fresh evidence consisted of an experiment conducted by a retired R.C.M.P officer, in which the circumstances of the shooting were simulated.  The Crown argued that the evidence was not of sufficient probative value, because it amounted to a speculative experiment with no scientific evidence. The British Columbia Court of Appeal rejected this argument, admitted the evidence and ordered a new trial stating, at 73:

In the result, I am satisfied that the appellant has met each of the tests required by [R. v. Palmer, 1979 CanLII 8 (SCC), [1980] 1S.C.R. 759].  As I have already indicated, the fresh evidence is capable of raising a reasonable doubt whether [the appellant] shot directly at [the victim] and a reasonable doubt whether the facts themselves prove that he did.  If accepted, and I do not think we can make that determination, the consequence would be a verdict of manslaughter, not second degree murder. 

[31]         In Toronto Helicopters Ltd. v. Intercity Ford Ltd. (1995), 18 M.V.R. (3d) 203 (Ont. Gen. Div.), a case arising out of a collision between the defendant’s tractor and the plaintiff’s helicopter, the plaintiff proposed to call evidence about stopping distances achieved in conditions that replicated the accident. The defendant objected to this experiment evidence on the ground that it constituted expert opinion evidence, and that proper notice had not been given pursuant to Rule 53.03 of the Ontario Rules of Civil Procedure. On a motion to exclude the evidence, the motions judge ruled that the evidence was admissible. Relying on various American texts, the motions judge held that the evidence was neither scientific evidence nor expert opinion evidence.  Rather, it was plain, factual testimony.

[32]         In R. v. Subhani, [1998] O.J. No. 1623 (Gen. Div.), the accused appealed from his conviction of the dangerous operation of a motor vehicle involving a high-speed night chase.  At trial, the only live issue was the identity of the driver. To rebut the eyewitness identification evidence, the defence sought to adduce expert opinion evidence, based on a series of experiments at a traffic intersection, that it would have been impossible for the eye witnesses to make out the facial features of the driver on the night in question.  The trial judge concluded that the expert’s testimony was of limited value due to a failure to precisely replicate the circumstances of the original night. On appeal, the appellant argued that the expert opinion was improperly rejected. Hill J., sitting as a summary conviction appeal court judge, disagreed, finding that the expert’s opinion was properly rejected because the subject-matter of his testimony was outside his area of expertise. Hill J. also made the following useful comment with respect to the assessment of this kind of evidence (at paras. 62-63):

 Where an expert witness purports to express opinion evidence founded on an experiment or recreation of events, the opinion will have probative value, more or less, depending on the integrity of the purported replication.  As in the instance of a hypothetical question posed to an expert witness, variances from the established facts of the original event(s), may, depending on materiality and degree of departure, substantially diminish the weight which can reasonably be afforded the expert’s evidence.  In an extreme case, admissibility itself may be jeopardized.

While no experiment or recreation can, as a general rule, exactly duplicate history, a lack of faithfulness to relevant and proven facts justifies caution by the trier-of-fact.  

[33]         R. v. Meads, [1996] Crim. L.R. 519 (C.A.) is one example of an English case where the distinction between factual testimony and expert opinion testimony is clearly made. Indeed, the ruling of the Court of Appeal in Meads is similar to the ruling made by the trial judge in this case. In Meads, the appellant was convicted of offences arising out of an armed robbery.  The principal evidence against him consisted of admissions and confessions allegedly made by him to the police during interviews.  On appeal, the appellant sought to adduce fresh evidence by forensic experts to show that the handwritten notes of the disputed interviews could not have been made in the time claimed by the interviewing officers. The prosecution argued against the admission of this evidence on the basis that the witness had insufficient experience to perform the tests.  In admitting the fresh evidence, the Court of Appeal was reported to have ruled as follows (at 520):

…the evidence was admissible provided that it was confined to tests performed by the two experts and the results of those tests.  It was not opinion evidence any more than the evidence of a police officer who gave evidence of timing a given journey in order to test an alibi.  The inference from such evidence – certain interviews having been apparently read back almost at the speed of a horse racing commentary – could be properly drawn by a jury.   

Les 5 questions qui doivent généralement trouver réponse pour qu'un juge puisse émettre une autorisation judiciaire

R. v. Adams, 2004 CanLII 12093 (NL PC)

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[24]  Generally speaking, there are five main questions which the issuing justice must ensure that an information to obtain a search warrant provides reasonable grounds to answer before he or she agrees to issue a search warrant:

1. that the items specified exist;

2. that the items specified will be found in the place to be searched at the time of the search;

3. that the offence alleged has been, or will be, (depending on the type of search warrant being sought) committed;

4. that the items specified will afford evidence of the offence alleged; and

5. that the place to be searched is the location where the items will be located.

[25]  In R. v. Colby, [1999] S.J. No. 915 (Q.B.), at paragraph 10, the essential elements of a C.D.S.A. warrant were described as follows:

...There must be reasonable and probable grounds for believing that the items to be searched for and seized are then in the place for which the warrant is to issue.  If that were not the case police relying on extremely outdated information, could seek and obtain a warrant to search a dwelling house.  Such was not the intention of the legislators.

Le procureur peut conseiller l'affiant dans la rédaction de son affidavit à l'appui d'une autorisation judiciaire sollicitée pour qu'il réponde aux normes établies par la jurisprudence

R. v. Ebanks, 2009 ONCA 851

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[49] While the Crown agent should help the affiant present the evidence in a clear and concise manner and point out any flaws, inconsistencies or ambiguities in the affidavit, he or she should not become an investigator and engage in a wholesale review of the file. This would blur the line between the mutually independent functions of the police and the Crown, each of whom properly maintains a distinct role in the criminal justice system.

L’autorisation de perquisitionner dans un lieu emporte celle de fouiller les espaces et contenants se trouvant dans ce lieu

R. v. Charles, 2012 ONSC 2001

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[61]           Defence counsel argued that the police had no power under the search warrant to open the safe, but rather were required to apply for a second warrant to examine its contents.  I disagree.  The search warrant empowered the police to search the apartment and its contents.  If, in the course of that search, they encountered a desk, they were empowered to look inside the desk.  That would include opening the drawers of the desk and looking inside those drawers.  They would not be required to get a new warrant if a desk drawer was locked.  The warrant provides them with all the authority they need to look inside the locked drawer.  There is nothing about a safe that makes it any different from a locked drawer.  There is every reason to believe that a person who is believed to be a drug dealer, who is found to have crack cocaine and a large amount of cash on his person, and who has a safe in his closet, is likely to have placed either drugs or proceeds or both in the safe.  Indeed, there is every reason to believe that is why he would have acquired a safe in the first place.

*** Note de l'auteur de ce blog: ce passage est cité avec approbation par R. c. Vu, 2013 CSC 60, par 39 ***

Principes régissant les mandats de perquisition et commentaires sur les fouilles d'ordinateurs

R. v Townsend, 2017 ONSC 3435

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Warrants

[53]           Prior to examining computer searches, a brief discussion of warrants is of benefit.  The face of the warrant is the document that empowers police to search a particular location for particular evidence:  Re Times Square Book Store and the Queen, 1985 CanLII 170 (ON CA), 21 C.C.C. (3d) 503; R. v. Parent, 1989 CanLII 217 (YK CA), 47 C.C.C. (3d) 385; R. v. Ricciardi, 2017 ONSC 2788; R. v. Merritt, 2017 ONSC 80.  The section of the warrant document known as the “Information to Obtain” provides an issuing justice the grounds to either grant or deny the police the right to search the location described on the face of the warrant for certain evidence.  However, the ITO is not part of the warrant that a searching officer is expected to examine.  Instead, the searching officer is only required to familiarize themselves with the face of the warrant in order to understand the parameters of the search.[4]  As a result of this interplay between the face of the warrant and the ITO, the face of the warrant is expected to satisfy what is known as the “fellow officer” test – that is, would a fellow officer be able to understand the items sought and the location to be searched as a result of reviewing the face of the warrant: R. v. Raferty, 2012 ONSC 703 at para 103.

[54]           In Ricciardi, Di Luca J. reviewed the guiding principles dealing with search warrants, searches pursuant thereto, and judicial review thereof. At paragraphs 12 to 17, Di Luca J. reviewed the law regarding the issuing of search warrants. At paragraphs 18 to 20, he then reviewed the law as it applies to the role of the reviewing judge:

                                    On a review, the role of reviewing judge is not substitute his or her view for that of the issuing justice. Rather, the role is to assess whether, on the basis of the material before the issuing justice as amplified and excised on review, the authorizing or issuing justice could have issued the warrant; see R. v. Sadikov, supra, at paras. 83-89, R. v. Ebanks, 2009 ONCA 851, R. v. Lao, 2013 ONCS 285 and R. v. Morelli, supra, at para. 40-41. As Watt J.A. explains in R. v. Mahmood, 2011 ONCA 693 at para 99:

      A reviewing judge does not substitute his or her view for that of the justice who issues the warrant. Rather, the reviewing judge considers the record before the issuing justice, but amplified by evidence adduced on the hearing to correct minor technical errors in drafting the ITO, to determine whether there remains sufficient credible and reliable evidence to permit the justice to issue the warrant.

                        The review is conducted based on the whole of the ITO using a common sense approach to all the circumstances. The review is not an exercise in picking apart the drafting of the ITO looking for minor imperfections, misstatements or omissions. While the police are required to draft an ITO as precisely and clearly as possible, they are not expected to spell things out as clearly as counsel. They are also not required to include every detail, no matter how minute, of the police investigation. The question is ultimately whether the core substance of the ITO could support issuance of the warrant; see R. v. Morelli at para 167, R.v. Lubell and the Queen (1973), 1983 CanLII 3587 (ON SC), 6 C.C.C. (3d) 296 (Ont. H.C.) at p. 190, Re Chapman and the Queen (1983), 6 C.C.C. (3d) 296 (Ont. H.C.) at p. 297, R. v. Ngyuen, supra, at para. 58, R v. Araujo (2000. 2000 SCC 65 (CanLII), 149 C.C.C. (3d) 449 (S.C.C.) and R.v. Persaud, 2016 ONSC 6815 at para. 64.

                        The excision exercise requires that any unlawfully obtained evidence be removed from consideration in assessing the sufficiency of grounds in an ITO, see R. v. Grant (1993), 1993 CanLII 68 (SCC), 84 C.C.C. (3d) 173 (S.C.C.), R. v. Plant (1993), 1993 CanLII 70 (SCC), 84 C.C.C. (3d) 203 (SCC) and R. v. Wiley 91993), 1993 CanLII 69 (SCC), 84 C.C.C. (3d) 161 (SCC). While the continued validity of the automatic exclusion approach has been criticized, it remains the law; see R. v. Jasser, 2014 ONSC 6052 at paras. 26-34.

Computer Searches and Warrants

[55]           Special interests are at play when the Courts examine the searches of computers.  Computers carry immense vaults of personal and biographical information.  The search of this information is, by definition, highly invasive.  As Fish J. stated in R. v. Morelli, 2010 SCC 8, [2010] 1 S.C.R. 253, at para 105:

As I mentioned at the outset, it is difficult to imagine a more intrusive invasion of privacy than the search of one's home and personal computer. Computers often contain our most intimate correspondence. They contain the details of our financial, medical, and personal situations. They even reveal our specific interests, likes, and propensities, recording in the browsing history and cache files the information we seek out and read, watch, or listen to on the Internet.

[56]           Typically, the right to search a location also provides the police with the right to search the receptacles within that location.  Unsurprisingly, given the heightened importance associated with the search of computers, the Supreme Court of Canada in Vu held that computers are different than other receptacles.  The Court stated at paras 40 to 45:

It is difficult to imagine a more intrusive invasion of privacy than the search of a personal or home computer: Morelli, at para. 105; R. v. Cole, 2012 SCC 53, [2012] 3 S.C.R. 34, at para. 3. Computers are "a multi-faceted instrumentality without precedent in our society": A. D. Gold, "Applying Section 8 in the Digital World: Seizures and Searches", prepared for the 7th Annual Six-Minute Criminal Defence Lawyer (June 9, 2007), at para. 3 (emphasis added). Consider some of the distinctions between computers and other receptacles.

First, computers store immense amounts of information, some of which, in the case of personal computers, will touch the "biographical core of personal information" referred to by this Court in R. v. Plant, 1993 CanLII 70 (SCC), [1993] 3 S.C.R. 281, at p. 293. The scale and variety of this material makes comparison with traditional storage receptacles unrealistic. We are told that, as of April 2009, the highest capacity commercial hard drives were capable of storing two terabytes of data. A single terabyte can hold roughly 1,000,000 books of 500 pages each, 1,000 hours of video, or 250,000 four-minute songs. Even an 80-gigabyte desktop drive can store the equivalent of 40 million pages of text: L. R. Robinton, "Courting Chaos: Conflicting Guidance from Courts Highlights the Need for Clearer Rules to Govern the Search and Seizure of Digital Evidence" (2010), 12 Yale J.L. & Tech. 311 at pp. 321-22. In light of this massive storage capacity, the Ontario Court of Appeal was surely right to find that there is a significant distinction between the search of a computer and the search of a briefcase found in the same location. As the court put it, a computer "can be a repository for an almost unlimited universe of information": R. v. Mohamad (2004), 2004 CanLII 9378 (ON CA), 69 O.R. (3d) 481, at para. 43.

Second, as the appellant and the intervener the Criminal Lawyers' Association (Ontario) point out, computers contain information that is automatically generated, often unbeknownst to the user. A computer is, as A.D. Gold put it, a "fastidious record keeper" (para. 6). Word-processing programs will often automatically generate temporary files that permit analysts to reconstruct the development of a file and access information about who created and worked on it. Similarly, most browsers used to surf the Internet are programmed to automatically retain information about the websites the user has visited in recent weeks and the search terms that were employed to access those websites. Ordinarily, this information can help a user retrace his or her cybernetic steps. In the context of a criminal investigation, however, it can also enable investigators to access intimate details about a user's interests, habits, and identity, drawing on a record that the user created unwittingly: O. S. Kerr, "Searches and Seizures in a Digital World" (2005), 119 Harv. L. Rev. 531, at pp. 542-43. This kind of information has no analogue in the physical world in which other types of receptacles are found.

Third, and related to this second point, a computer retains files and data even after users think that they have destroyed them.

                        …

Computers thus compromise the ability of users to control the information that is available about them in two ways: they create information without the users' knowledge and they retain information that users have tried to erase. These features make computers fundamentally different from the receptacles that search and seizure law has had to respond to in the past.

Fourth, limiting the location of a search to "a building, receptacle or place" (s. 487(1) of the Code) is not a meaningful limitation with respect to computer searches. As I have discussed earlier, search warrants authorize the search for and seizure of things in a "building, receptacle or place" and "permit the search of receptacles such as a filing cabinets, within that place…. The physical presence of the receptacle upon the premises permits the search": Fontana and Keeshan, at p. 1181 (italics in original; underling added). Ordinarily, then, police will not have access to items that are not physically present in the building, receptacle or place for which a search has been authorized. While documents accessible in a filing cabinet are always at the same location as the filing cabinet, the same is not true of information that can be accessed through a computer. The intervener the Canadian Civil Liberties Association notes that, when connected to the Internet, computers serve as portals to an almost infinite amount of information that is shared between different users and is stored almost anywhere in the world. Similarly, a computer that is connected to a network will allow police to access information on other devices. Thus, a search of a computer connected to the Internet or a network gives access to information and documents that are not in any meaningful sense at the location for which the search is authorized.

These numerous and striking differences between computers and traditional "receptacles" call for distinctive treatment under s. 8 of the Charter. The animating assumption of the traditional rule -- that if the search of a place is justified, so is the search of receptacles found within it -- simply cannot apply with respect to computer searches.

[57]           The Supreme Court of Canada then considered whether or not a properly authorized warrant to search required search parameters. In holding that search parameters were not constitutionally required, the Court stated at paras 53 and 54 of Vu:

The intervener the British Columbia Civil Liberties Association (“B.C.C.L.A.”) submits that, in addition to a requirement that searches of computers be specifically authorized by a warrant, this Court should also find that these warrants must, as a rule, set out detailed conditions, sometimes called "ex ante conditions" or "search protocols", under which the search may be carried out. According to the B.C.C.L.A., search protocols are necessary because they allow authorizing justices to limit the way in which police carry out their searches, protecting certain areas of a computer from the eyes of the investigators. The Crown and intervening Attorneys General oppose this sort of requirement, arguing that it is contrary to principle and impractical. While I am not convinced that these sorts of special directions should be rejected as a matter of principle, my view is that they are not, as a general rule, constitutionally required and that they would not have been required in this case.

While I propose, in effect, to treat computers in some respects as if they were a separate place of search necessitating distinct prior authorization, I am not convinced that s. 8 of the Charter requires, in addition, that the manner of searching a computer must always be spelled out in advance. That would be a considerable extension of the prior authorization requirement and one that in my view will not, in every case, be necessary to properly strike the balance between privacy and effective law enforcement….

[58]           However, the Court did indicate at paras 61 and 62 that parameters may be preferable in certain situations:

By now it should be clear that my finding that a search protocol was not constitutionally required in this case does not mean that once police had the warrant in hand, they had a licence to scour the devices indiscriminately. They were bound, in their search, to adhere to the rule that the manner of the search must be reasonable. Thus, if, in the course of their search, the officers realized that there was in fact no reason to search a particular program or file on the device, the law of search and seizure would require them not to do so.

Although I do not find that a search protocol was required on the particular facts of this case, authorizing justices must assure themselves that the warrants they issue fulfil the objectives of prior authorization as established in Hunter. They also have the discretion to impose conditions to ensure that they do. If, for example, an authorizing justice were faced with confidential intellectual property or potentially privileged information, he or she might find it necessary and practical to impose limits on the manner in which a computer could be searched. In some cases, authorizing justices may find it practical to impose conditions when police first request authorization to search. In others, they might prefer a two-stage approach where they would first issue a warrant authorizing the seizure of a computer and then have police return for an additional authorization to search the seized device. This second authorization might include directions concerning the manner of search. Moreover, I would not foreclose the possibility that our developing understanding of computer searches and changes in technology may make it appropriate to impose search protocols in a broader range of cases in the future. Without expressing any firm opinion on these points, it is conceivable that proceeding in this way may be appropriate in some circumstances.

[59]           The Ontario Court of Appeal had considered the “license to scour” a computer described in Vu, in R. v. Jones, 2011 ONCA 632, 107 O.R. (3d) 241.  In Jones, the police seized a computer and searched pursuant to a broadly worded warrant.  In searching the computer, the police analyst discovered child pornography.  The police relied upon the initial warrant to conduct a further search.  The Crown argued on appeal that a computer was an indivisible item and that once police had authority to search the computer, the police could search the entire computer. 

[60]           Blair J.A., writing for the Court, rejected this argument and stated at paragraph 50: 

The police have available to them the necessary software, technology and expertise to enable them to tailor their searches in a fashion that will generate the information they seek, if it exists, while at the same time minimizing the intrusion on the computer user's privacy rights in other information stored on the computer. Sergeant Rumnyak testified that the EnCase software used in this case permits the police to view all data and all files contained on the computer but that the police do not normally look at all files in the course of an investigation; they focus on those they think will generate the evidence they are looking for. That is as it should be.