Canadian Criminal Procedure and Practice/Trials/Opening and Closing Submissions
Opening submissions 
Inflamatory remarks during opening submissions may allow for a mistrial.
- Stewart v. Speer (1953),  O.R. 502 (Ont. C.A.)
Landolfi v. Fargione (2006), 2006 CarswellOnt 1855 (Ont. C.A.)
Closing submissions 
Both counsel have a "fair degree of latitude" on their closings. They are each entitled to "advance his ... position forcefully and effectively", it is expected that there will be "a degree of rhetorical passion in that presentation." 
However, the Crown must: 
- "abstain from inflammatory rhetoric",
- abstain from "demeaning commentary and sarcasm",
- not "misstate the law",
- "not invite the jury to engage in speculation" 
- not "express personal opinions about either the evidence or the veracity of a witness" 
Violations of these requirements may sometimes result in a mistrial. However, the prejudices arising from this conduct can often be remedied by additional jury instructions.
A judge must allow counsel an opportunity to make closing submission in full. Nevertheless, the judge can still comment on the evidence during the submissions and may attempt at focusing the argument on particular issues of concern. The judge cannot prevent counsel from making submissions on relevant issues. A trial judge does not have to be silent during submissions and can voice concerns. He is permitted to express a preliminary opinion on the evidence or the law during submissions.
Where counsel makes false or erroneous submissions in the address to a jury, the judge must give corrections in the jury instruction.
The party calling a witness does not need to assert that the trier of fact accept everything said by the witness wholesale.  Crown counsel is entitled to invite the trier of fact to be selective of the evidence they chose to believe from the witness that the Crown called. Crown counsel can ask that the trier reject evidence of a Crown witness in preference of other evidence heard. However, counsel cannot ask for the rejection of evidence in favour of a theory not in evidence. Likewise, a party is not precluded from calling evidence that may contradict other witnesses called by the same party.
Once the Crown has completed their evidence, it is not allowed to change it's theory of the case because of the addition of defence evidence.
Submissions by counsel on issues before the court cannot be intentionally or inadvertently denied by the court. A failure would result in a new trial.
- R. v. Daly, (1992), 57 O.A.C. 70, at p. 76
R. v. Boudreau, 2012 ONCA 830 (CanLII) at para. 15 onward
see also R. v. Mallory, 2007 ONCA 46 (CanLII), 217 C.C.C. (3d) 266 , at para. 339
- R. v. Boudreau, 2012 ONCA 830 (CanLII) at para. 16
Mallory 2007 ONCA 46
- see Mallory, at para. 340
- see Mallory, at para. 340
- R. v. Boudreau, 2012 ONCA 830 (CanLII) at para. 20
- R. v. Al-Fartossy, 2007 ABCA 427, 425 A.R. 336 at para. 25
- R. v. Hodson, 2001 ABCA 111 at paras. 33 and 35
- R. v. W.F.M. (1995), 169 A.R. 222 (C.A.) at para. 10
- R. v Baccari, 2011 ABCA 205 at para. 24
R. v Johnson, 2010 ABCA 392 at para. 14
- see R. v. Romeo, 1991 CanLII 113 (SCC),  1 S.C.R. 86 at para. 95
R. v. Rose, 1998 CanLII 768 (SCC),  3 S.C.R. 262 at paras. 126 and 127
- R. v. Benji, 2012 BCCA 55 at 158
R. v. Biniaris, 1998 CanLII 14986 (BC CA) at 9
- R. v. Walker, 1994 CanLII 8725 (ON CA) at 156
- Walker at 157
- R. v. Biniaris, 1998 CanLII 14986 (BC CA) at 10 citing Cariboo Observer Ltd. v. Carson Truck Lines Ltd. and Tyrell (1961), 32 D.L.R. (2d) 36 at 39, 37 W.W.W. 209 (B.C.C.A.)
- R. v. G.(S.G.), 1997 CanLII 311 (SCC),  2 S.C.R. 716
- Dewey v. Dawson-Moran, 2011 ABCA 45 at 12
R v Komarnicki, 2012 SKQB 140