…the presence of a party at the examination for discovery, like the presence of a party at trial, is consistent with due process and the right to protect his or her interests by observing the conduct of the examination
The law in Ontario is that a party has a right to be present at the examinations for discovery of a co-party, except for cause.
What constitutes Cause is determined on the circumstances of each case.
In the 2019 decision of Horizon Entertainment Cargo Ltd. v. Marshall, a motion was brought to exclude the defendants from attending each other’s examination for discovery. This also included being told about the evidence or reading the transcript evidence before their own discovery.
The Master presiding over the motion stated that:
In order to obtain an exclusion order, the moving party must demonstrate that the exclusion is necessary to meet the ends of justice (Baywood Paper Products Ltd. v. Cheque-Writers (Canada) Ltd. and adopted in Lazar v. TD General Insurance Co. (Div. Ct.). A party cannot be excluded from examinations for discovery except for cause. What may constitute cause depends on the circumstances of each case.
The Court, in making the decision, considered the following:
(a) do the co-parties have common interests;
(b) are the co-parties represented by the same lawyer;
(c) whether it appears the examinations for discovery will cover the same grounds;
(d) will credibility will be a factor or an issue; and
(e) the likelihood that a party will tailor his or her evidence as a result of being privy to the evidence given by his or her co-party
It was concluded that the Plaintiff had not “demonstrated that the ends of justice require an exclusion order” and accordingly, the motion was declined and costs were awarded to the Defendants.
In the usual course of examinations for discovery, typically in personal injury cases, parties do not sit in on the other side’s discovery evidence, but it is a right that can be exercised and is the law in Ontario. It is sometimes a tactical decision, based on the case, or because a party genuinely wants to be present through the entire proceeding.