Lost or Destroyed Evidence
Where evidence is in the possession of the Crown or Police, there is a duty to preserve this evidence. Where this evidence goes missing or is destroyed, it can in certain circumstances, form grounds for a stay of proceedings under s. 7 and 11(d) of the Charter. The stay is on the basis that the rights under s. 7 of the Charter to make full answer and defence and under s. 11(d) to a fair trial have been violated.
There is a limited right to review original documents. Where the originals have gone missing the Crown has an obligation to explain how it went missing.
Reason for Loss
The loss of evidence will not result in the a breach of duty to disclose so long as the conduct of police was reasonable.
Not every instance where negligence that results in the loss of evidence will result in a Charter breach.
Not every case loss of evidence will infringe the accused’s right to make full answer and defence. “Owing to the frailties of human nature, evidence will occasionally be lost” . The Crown must explain the loss and satisfy the trial judge that it was not due to unacceptable negligence or an abuse of process. If satisfactorily explained, the onus is on the accused to “establish actual prejudice to his or her right to make full answer and defence” . The principal consideration, in the explanation, “is whether the Crown or the police (as the case may be) took reasonable steps in the circumstances to preserve the evidence” 
There can only be a breach of the duty to disclose where the loss or destroyed evidence was found to due to "unacceptable negligence"  A reach of this duty will result in a violation of s. 7 of the Charter. Additionally, it may amount to an abuse of process. The only available remedy would be a stay.
Even where it does not amount to "unacceptable negligence", there may still be a breach of section 7 of the Charter where " the loss can be shown to be so prejudicial to the right to make a full answer and defence that it impairs the right to a fair trial. " The only available remedy would be a stay.
Notice of Destruction
Notifying the accused ahead of destruction of property inviting inspection may cure the prejudice cause by the loss of evidence from the destruction of property.
Discarding of the mouthpiece used in an alcohol roadside screening device will not violate the right to full answer and defence under s. 7 of the Charter.
Lost Court Record
The loss or destruction of the recording and transcripts of a preliminary inquiry will be sufficient for an acquittal due to failure to make full answer and defence.
Destruction by Third Party
Where records held by a third party are destroyed there may be a stay of proceedings.
R v FCB, 2000 NSCA 35 (CanLII), 142 CCC (3d) 540 at 547-48 (N.S. C.A.)
R v Bero, 2000 CanLII 16956 (ON CA) at para 30
- R v La 1997 CanLII 309 (SCC),  2 SCR 680 at para 21
R v Lipovetsky, 2007 ONCJ 484 (CanLII),  O.J. No. 4135 at para 19 ("Even where there is negligence on the part of the Crown, the loss of a videotape does not automatically violate the Charter. A Charter breach is established only where the lost evidence is shown by the applicant to be relevant to the issues at trial.")
See also R v Dulude, 2004 BCPC 524 (CanLII),  O.J. No. 3576 (C.A.) at para 30
- R v La, 1997 CanLII 309 (SCC),  2 SCR 680, at para 20
- La at para 25
- La at para 21
and see R v Kociuk (R.J.), 2011 MBCA 85 (CanLII)
Bero, at para 30
Bero at para 30
Bero at para 30
- Bero at para 30
Bero, at para 30
- e.g. R v Berner, 2012 BCCA 466 (CanLII) - car in collision destroyed by police prior to trial. Officer sent registered mail letter to accused prior to releasing vehicle.
R v Lee, 2010 ONSC 4117(*no CanLII links)
R v Boylan, 2011 BCPC 235 (CanLII)
R v Goosen, 2014 SKQB 135 (CanLII)
c.f. R v Dhillon, (1999), 41 W.C.B. (2d) 48(*no CanLII links) - stay of proceedings
- R v MacLeod, 1994 CanLII 5243 (NB CA), (1994), 93 CCC (3d) 339 (N.B.C.A.)
- R v Carosella, 1997 CanLII 402 (SCC),  1 SCR 80 - rape crisis centre destroyed nurses notes per centre's policy
Lost Statements of the Complainant
When considering whether a stay is appropriate for a lost statement, the Court should consider "all the surrounding background facts and circumstances of the complainant's evidence" such as:
- "the emotional or psychological status of the complainant at the time the allegations were made"
- "the time when the complaints were made in relation to when the allegations occurred, i.e. before or after therapy"
- "whether the investigating officers who took the statement were available for questioning"
- "whether the complainant made other statements prior to trial that the defence can use to attack her credibility"
- "whether the Crown concedes that proposed substitute evidence is a statement of the complainant and may be used for the purposes of cross-examination of the complainant"
- "whether the statements that do exist appear to contain the same amount of detail as the lost statement"
- "the extent of the complainant's present ability to recall the contents of the earlier statements"
- "the complainant's present ability to recall the details surrounding the various alleged incidents of abuse"
- "any apparent or potential inconsistencies in the complainant's trial testimony or between her other statements and her evidence at the preliminary hearing"
- "whether the accused was made aware of the contents of the lost evidence before its destruction or disappearance"
- "whether the Crown gave any undertaking to the accused at the time that matters would not proceed with the result that the accused did not retain his own records" and
- "what other witnesses had to say at the time in support or contradiction of the complainant's allegations"
Emphasis of consideration should be on "whether other available evidence contains essentially the same information as the lost evidence".