General Principles
Presumption of Propriety
In a jury trial, it is presumed that jurors will perform their duties according to their oath or solemn affirmation. But this presumption of impartiality is rebuttable. R v Pannu, 2015 ONCA 677, at para 61; see also R v Zvolensky, 2017 ONCA 273 at paras 230-242
It is also presumed that jurors understand and follow the instructions they are given. This presumption is also rebuttable: Pannu at para 61
Misconduct during deliberations
Section 647(2) of the Criminal Code mandates that when a jury is sequestered:
[T]he jury shall be kept under the charge of an officer of the court as the judge directs, and that officer shall prevent the jurors from communicating with anyone other than himself or another member of the jury without leave of the judge.
The purpose of this section is to protect jurors from outside influences that might affect their verdict. This section does not require that all twelve jurors must all be together at all times, unless they are in their hotel rooms alone. Jurors should be encouraged to relax when they are It is undoubtedly a good practice for trial judges to tell jurors not to deliberate when they are not all together. However, some casual comment about the case while some of them are in smaller groups does not amount to a miscarriage of justice. These are a diverse group of people compelled to be with each other, and the only thing they have in common is the trial. It may well happen that someone will comment on the evidence while one juror is in the washroom, for example. The requirement of unanimity for a verdict removes any concern about such comments.
Where there is no evidence that a juror’s ability to do their job has been impaired by alcohol, consumption of alcohol by a juror with or after dinner is no basis to set aside a verdict: R v Zvolensky, 2017 ONCA 273 at paras 233-238
Extrinsic Misconduct
Evidence clearly establishing the presence of extrinsic material during deliberations can displace the presumption that jurors will perform their duties according to their oath or solemn affirmation: see generally R v Lewis, 2017 ONCA 177, at para 36
Juror Secrecy Rule
Preservation of the secrecy of jury deliberations is of vital importance to the proper administration of criminal justice. The rule helps to ensure that jurors feel comfortable freely expressing their views in the jury room. If jurors know that the views they express in the jury room may eventually come to light, they may be less inclined to argue for a verdict that may be perceived as unpopular.
For example, a juror who has serious concerns about the foundations of a conviction might rapidly accede to the majority viewpoint of convicting an accused charged with a horrible crime rather than attempt to argue for, or even explore out loud, the arguments favouring an acquittal, fearful of possible negative public exposure.
The jury secrecy rule is also important to the assure finality and the authority of a verdict.
A court cannot, therefore, receive or adjudicate upon statements or affidavits by any member of a jury as to their deliberations or intentions on the case: R v Lewis, 2017 ONCA 177, at para 37-43