7.8 Previous Convictions of Witness or Third Party as Evidence of Disposition
(Last revised March 2011)
-  You have heard that (NOW)/(NO3P) might have committed the offence charged.
-  (NOW)/(NO3P) has previously been convicted of (describe nature of prior conviction). This may help you decide whether (NOW)/(NO3P) is the sort of person who would commit the offence with which (NOA) is charged.
-  Evidence that (NOW)/(NO3P) is the sort of person who would commit the offence charged might, along with other evidence, cause you to have a reasonable doubt about whether it was (NOA) who committed it.
-  At the end of this trial, I will explain in greater detail how you may use this and other evidence relating to (NOW)/(NO3P).
 Any person charged with an offence may adduce evidence that tends to show that a co-accused committed the offence provided it has sufficient probative value to justify its admission: R v Grandinetti,  1 SCR 27. The evidence may be direct or circumstantial. It may include, but cannot consist only of, evidence of the third party’s motive or disposition to commit the offence. Without some other connection of the co-accused to the offence charged, however, evidence of motive or disposition is not admitted because it lacks probative value.
This instruction should only be given in cases where the trial judge is satisfied:
- (i) that there is evidence, other than evidence of disposition, which sufficiently connects the co-accused to the offence charged to warrant admission of the disposition evidence; and
- (ii) that the proposed evidence, whether of expert opinion, discrete acts of extrinsic misconduct, or both, alone or together with other evidence, is relevant and of sufficient probative value on the issue of disposition to justify its admission.
See R v McMillan (1975), 23 CCC (2d) 160, 167-8 (Ont. C.A.), per Martin J.A.