This issue was considered at length during the last Parliament. Essentially we looked at how to attest to the quality of the signature, or the legitimacy of the signature, and at that time the committee adopted certain elements to determine which types of signatures are not acceptable, such as, for instance, all signatures that end with gc.ca, meaning people signing from their offices in government. A couple of filters like that exist to attest to the legitimacy of the signatures.
On February 28th, 2019. See this statement in context.