Can a court order a handwriting or forensic document expert in an Ontario will dispute?

Yes. Where a genuine question exists about whether a signature on a will is authentic, whether a document was altered after signing, or whether a holograph will is really in the testator's own handwriting, a party to an Ontario will dispute can retain a forensic document or handwriting expert, and the court can permit or, in some circumstances, direct expert evidence on the point as part of the litigation process, much like expert evidence is used in other types of civil cases involving disputed documents.

This kind of expert evidence usually involves comparing the disputed signature or handwriting against verified samples from the testator, and can also examine physical characteristics of the document itself, such as ink, paper, or signs of alteration. It's not used in every will challenge — only where authenticity or alteration is genuinely in issue, rather than in disputes primarily about capacity or undue influence where the signature itself isn't disputed. Because retaining a qualified forensic expert and gathering enough verified comparison samples takes time, and expert reports must generally be exchanged according to the court's procedural timelines before trial, anyone who suspects a signature or handwriting issue should raise it with a lawyer as early as possible in the case.