Justification for detention
In Canada, there are only three grounds for detaining an accused prior to sentence. They are commonly referred to as primary grounds, secondary grounds, and tertiary grounds.
Primary grounds refers to whether detention is necessary to ensure the accused's attendance in court.] Considerations include the accused's criminal history, their behaviour in the matter before the court, their connections (or lack of) with the jurisdiction, and the type of offences before the court.
Secondary grounds refers to whether detention is necessary for the protection or safety of the public. This includes whether there is a substantial likelihood the accused will commit a further offence or interfere with the administration of justice.]
Tertiary grounds refers to whether detention is necessary to maintain confidence in the administration of justice, and is generally reserved for very serious offences. The four factors to consider are:
- the apparent strength of the prosecutor's case,
- the seriousness of the offence,
- the circumstances surrounding the offence, including whether a firearm was used, and
- if found guilty, whether the accused is liable to a potentially lengthy term of imprisonment, or if a firearm was involved, faces a minimum of 3 year of jail.
- v.St-Cloud, 2015 SCC 27,  2 S.C.R. 328
- v. Hall, 2002 SCC 64
Hearsay evidence is generally inadmissible in Canada unless it falls within one of the established common law exceptions. As a result of the Supreme Court's decision in R. v. Khan 1990] 2 S.C.R. 531 and subsequent cases, hearsay evidence that does not fall within the established exceptions can be admitted where established that such evidence is both "necessary and reliable". Additionally, hearsay evidence that would otherwise be admissible as an exception can nonetheless be excluded if it is not necessary and reliable, as in R. v. Starr  2 S.C.R. 144.
Search Warrants – Issuing and Review
Issuing of Warrant: Reasonable and Probable Grounds
The Charter requires that for all warrants police must provide "reasonable and probable grounds, established upon oath, to believe that an offence has been committed and that there is evidence to be found at the place of the search" These requirements set out the "minimum standard, consistent with s. 8 of the Charter, for authorizing search and seizure"
In more recent times the standard is called "reasonable grounds to believe". 
The standard of reasonable grounds to believe is greater than mere suspicion but less than on a balance of probabilities when the totality of the circumstances are considered. It is a standard of reasonable probability and is credibility based. It must be more than mere possiblity or suspicion. It is a standard of "credibly-based probability" 
The key elements to credibility-based probability includes:
- The Information to obtain the warrant must set out sworn evidence sufficient to establish reasonable grounds for believing that an offence has been committed, that the things to be searched for will afford evidence and that the things in question will be found at a specked place
- The Information to obtain as a whole must be considered and peace officers, who generally will prepare these documents without legal assistance, should not be held to the "specificity and legal precision expected of pleadings at the trial stage."
- The affiant's reasonable belief does not have to be based on personal knowledge, but the Information to obtain must, in the totality of circumstances, disclose a substantial basis for the existence of the affiant's belief: R. v. Yorke 1992 CanLII 2521 (NS CA), (1992), 115 N.S.R. (2d) 426 (C.A.); affd 1993 CanLII 83 (SCC),  3 S.C.R. 647.
The court may consider the experience of a police officer when assessing whether the officer's subjective belief was objectively reasonable.
The Justice of the Peace may draw reasonable inferences from the information found in the ITO.
The approving justice must be satisfied that there is a connection between the grounds for belief of the offence and that evidence of or information related to the offence will be found on the premises to be searched.
The Information to Obtain the search warrant (ITO) does not need to state every step a police officer takes in obtaining information.
An ITO can be read in a practical, non-technical, common-sense fashion.
The officer's are not held to the same drafting quality as counsel.
The document should be reliable, balanced and material. It should also be clear, concise, legally and factually sufficient, but it need not include "every minute detail of the police investigation". 
The ITO cannot be based on any information that was learned through an warrantless search of an agent of the state.
Where the basis of the warrant relies on a confidential informer, the requirement from R v Debot must be considered. Generally, the requirement will increase "the level of verification required" where "credibility cannot be assessed", "fewer details are provided", and "the risk of innocent coincidence is greater". 
Generally, an approving justice should be satisfied that:
- that the items specified exist;
- that the items specified will be found in the place to be searched at the time of the search;
- that the offence alleged has been, or will be, (depending on the type of search warrant being sought) committed;
- that the items specified will afford evidence of the offence alleged; and
- that the place to be searched is the location where the items will be located.
The document should be reliable, balanced and material. It should also be clear, concise, legally and factually sufficient, but it need not include "every minute detail of the police investigation" 
- Hunter v. Southam Inc., 1984 CanLII 33 (SCC), 1984 CanLII 33 (SCC),  2 S.C.R. 145, at p. 168
See also R. v. Vella (1984) 14 CCC 513
R. v. Harris, 1987 CanLII 181 (ON CA)
- Hunter v Southam at p. 168
- Mugesera v. Canada (Minister of Citizenship and Immigration), 2005 SCC 40 at para. 114
- ibid.; R. v. Le 2006 BCCA 298; 2006 BCCA 463
- Hunter et al v. Southam Inc., 1984 CanLII 33 (SCC),  2 S.C.R. 145
Baron v. Canada, 1993 CanLII 154 (SCC),  1 S.C.R. 416)
- R. v. Hosie  O.J. No. 2175 (ONCA) at para. 11; Hunter v. Southam Inc., 1984 CanLII 33 (SCC),  2 S.C.R. 145 at p. 167
- R. v. Morris 1998 CanLII 1344 (NS CA), (1998), 173 N.S.R. (2d) 1 (C.A.) at para. 31
- R. v. Sanchez 1994 CanLII 5271 (ON SC), (1994), 93 C.C.C. (3d) 357 (Ont. Ct. Gen. Div.) at 365
- Sanchez, supra, at 364
- R v. MacKenzie 2011 SKCA 64 at para. 27, see also R v. Navales 2011 ABQB 404
R. v. Sanchez (1994), 93 C.C.C. (3d) 537 (Ont.Gen. Div.)
- See R. v. Durling, 2006 NSCA 124 (CanLII) at paras. 27-28; R. v. Vu at para. 40
- R. v. Turcotte 1987 CanLII 984 (SK CA), (1987), 39 C.C.C. (3d) 193 (Sask.C.A)
- R. v. Sanchez,  OJ No. 2260 at para. 20
- R. v. Whitaker, 2008 BCCA 174 at 41-42
- Re Lubell and the Queen (1973), 11 C.C.C. (2d) 188 (Ont. H.C.), at p.190;
R. v. Durling 2006 NSCA 124 , (2006), 214 C.C.C. (3d) 49 (N.S.C.A.), at para. 19;
R. v. Sanchez 1994 CanLII 5271 (ON SC), (1994), 93 C.C.C. (3d) 357 (Ont. Ct. Gen. Div.), at p. 364;
Re Chapman and the Queen, (1983), 6 C.C.C. (3d) 296 (Ont. H.C.), at p. 297.
- C.B.C. v. A.-G. for New Brunswick 1991 CanLII 50 (SCC), (1991), 67 C.C.C. (3d) 544 (S.C.C.), at p. 562
R. v. Araujo 2000 SCC 65, (2000), 149 C.C.C. (3d) 449 (S.C.C.), at p. 470;
R. v. Ling 2009 BCCA 70, (2009), 241 C.C.C. (3d) 409 (B.C.C.A.), at para. 43 (leave to appeal refused,  S.C.C.A. No. 165)
- R. v. Hosie  O.J. No. 2175 (ONCA) at para. 12
See R. v. Debot 1989 CanLII 13 (SCC), 1989 CanLII 13 (SCC), (1989), 52 C.C.C. (3d) 193 at page 215 (S.C.C.)
- R v Debot, at page 218
- R v Adams 2004 CanLII 12093 (NL PC) at para. 24
- C.B.C. v. A.-G. for New Brunswick 1991 CanLII 50 (SCC), (1991), 67 C.C.C. (3d) 544 (S.C.C.), at p. 562
R. v. Araujo 2000 SCC 65 (CanLII), (2000), 149 C.C.C. (3d) 449 (S.C.C.), at p. 470
R. v. Ling 2009 BCCA 70 (CanLII), (2009), 241 C.C.C. (3d) 409 (B.C.C.A.), at para. 43 (leave to appeal refused,  S.C.C.A. No. 165)
Standard of Review: The Garofoli Application
A "Garofoli Application" refers to the defence motion to exclude evidence collected under a search warrant.
Before a party can make such an application, they must have standing, which requires that there be an established Reasonable Expectation of Privacy.
Presumptions and Burdens
A warrant is presumed valid. The applicant bears the burden to establish that there was insufficient basis for issuing the warrant.  This presumption applies not only to the warrant but the ITO as well.
Degree of Deference
The reviewing judge is not examining police conduct with great attention to minor details or dissection.  Rather the judge must look at whether there is sufficient evidence for the warrant.
The test on review is not whether the reviewing judge would have granted the warrant but whether there was "reliable evidence that might reasonably be believed" on which the warrant could have been issued.
The reviewing judge should not "substitute his or her own view for that of the authorizing judge."
A search of a private premises "is a derogation from common law rights of ownership. The necessary formalities in the execution of the warrant must, therefore, be strictly observed".
Errors in the information, "whether advertent or even fraudulent, are only factors to be considered in deciding to set aside the authorization and do not by themselves lead to automatic vitiation of the ... authorization."
The ITO is examined as a whole and not one piece of evidence at a time. 
Excised Portions of ITO
Inaccurate or omitted information in an ITO does not necessarily render it invalid.
Inaccurate information can be excised from the ITO, and re-evaluated without the offending information.
Where information was omitted from an ITO or where information has been excised for other reasons, it is possible to remedy it by adducing amplification evidence.
This form of evidence can be adduced to correct innocent, minor or technical errors.
- R. v. Campbell, 2010 ONCA 558, at para. 45. (aff'd, 2011 SCC 32)
R v Shier,  OJ No 5751 at para. 48
Quebec (Attorney General) v. Laroche, 2002 SCC 72 (CanLII),  3 S.C.R. 708
- R v Collins (1989) 48 CCC (3d) 343 at p. 356
- R. v. Grant 1999 CanLII 3694 (ON CA), (1999), 132 C.C.C. (3d) 531 (Ont. C.A.) at 543 (leave to appeal refused  S.C.C.A. No. 168 (Q.L.), 150 C.C.C. (3d) vi); R. v. Chan,  O.J. No. 4536 (Q.L.) at para. 4, 40 W.C.B. (2d) 143 (C.A.)
R. v. Melenchuk and Rahemtulla,  B.C.J. No. 558 at para. 15-18
Simonyi Gindele et al. v. British Columbia (Attorney General) (1991), 2 B.C.A.C. 73 (C.A.) at 79.
- R. v. Nguyen, 2011 ONCA 465 at 57
- R. v. Araujo, 2000 SCC 65 (CanLII),  2 SCR 992 at para. 54
See also R. v. Witaker 2008 BCCA 174
R. v. Garofoli, 1990 CanLII 52 (SCC),  2 SCR 1421 at para. 56
R. v. Grant, 1993 CanLII 68 (SCC),  3 SCR 223 at para. 49
R v. Veinot (1995), 144 N.S.R. (2d) 388 (C.A.) at p. 391, 1995 CanLII 4262
R v Morelli, 2010 SCC 8 at para. 40
- R v Garofoli 1990 CanLII 52 (SCC)
- R. v. B.(J.E.), (1989), 52 C.C.C. (3d) 224 (N.S.C.A.)
- Nguyen, at 58
- R v Pires 2005 SCC 66 at 30
- R. v. Bisson, 1994 CanLII 46 (S.C.C.),  3 S.C.R. 1097; (1995), 94 C.C.C. (3d) 94 at p. 1098
- R. v. Whitaker, 2008 BCCA 174
R. v. Brachi, 2005 BCCA 461
Re Church of Scientology & the Queen (No. 6) 1987 CanLII 122 (ON CA), (1987), 31 C.C.C. (3d) 449 (Ont. C.A.))
- See R v Bisson 1994 CanLII 46 (SCC),  3 SCR 1097, (1994) 94 CCC (3d) 94 at pp. 95-96
R. v. Budd, 2000 CanLII 17014 (ON CA) at para. 20-23
R. v. Agensys International Inc., 2004 CanLII 17920 (ON CA) at para. 32