The defence has closed its case when suddenly the client advises their lawyer of a very important issue that needs to be addressed such as a helpful witness, a relevant document or some other factor of significance. In this scenario, can the defence ask to reopen its case? If the judge has already convicted the client, is it now too late to reopen the case?
Examining precedent regarding reopening the defence and precedent pertaining to the admissibility of new evidence sheds light on the questions raised in this scenario.
The test for reopening the defence case when the application is made prior to conviction has been laid down in Hayward (Ont. C.A.),  O.J. No. 2939:
17 When faced with an application to reopen the evidence, the trial judge should first be satisfied that the proposed evidence is relevant to a material issue in the case. That determination can usually be made on the basis of counsel’s summary of the anticipated evidence…
18 Once it is determined that the proposed witness has relevant evidence to give, the trial judge must consider the potential prejudice to the other party should he or she permit the reopening of the evidence…
19 The trial judge must also consider the effect of permitting a reopening of the evidence on the orderly and expeditious conduct of the trial. It does not appear from this record that permitting Mr. Fisher to testify would have had any significant negative impact on the progress of the trial. The trial judge did not advert to any such negative consequences in his refusal of the application. The evidence had finished only an hour earlier, and it seems likely that Mr. Fisher’s evidence would have been relatively brief. Also, while some additional argument may have been necessary following Fisher’s evidence, there would have been no need to repeat arguments already made. I see no reason why the trial would not have been completed within the same day.
Additionally, once the trial judge has convicted the accused, a more rigorous test is required to protect the integrity of the process, including the enhanced interest in finality. Then the test for the admissibility of fresh evidence on appeal laid down in Palmer and Palmer v. The Queen (1979), 50 C.C.C. (2d) 193, at page 205 (S.C.C.) (see: R. v. Mysko (1980), 2 Sask.R. 342 (C.A.).) That test is as follows:
– (1) the evidence should generally not be admitted if, by due diligence, it could have been adduced at trial provided that this general principle will not be applied as strictly in a criminal case as in civil cases …;
– (2) the evidence must be relevant in the sense that it bears upon a decisive or potentially decisive issue in the trial;
– (3) the evidence must be credible in the sense that it is reasonably capable of belief;
– (4) it must be such that if believed it could reasonably, when taken with the other evidence adduced at trial, be expected to have affected the result.
Based on the above, there are many factors that must be considered before reopening the defence, including consideration of the relevance and credibility of the evidence in question, any prejudices to the other party which could arise from reopening the matter and the potential impact on the progress of the trial.