Annulment is not the same as civil divorce.
Civil divorce in Canada must be obtained before applying for an annulment. Divorce addresses the legal effects of marriage in civil law. A declaration of nullity asks a different question: whether a true marriage was ever validly formed in the eyes of the Church.
As with any court, the person bringing a matter before the tribunal must prove the case. Not every application is successful. The tribunal must distinguish unions that were flawed from the outset from valid marriages that later broke down.
When a petition is introduced, the tribunal examines whether one or both parties may have given invalid consent at the time of marriage. This discernment is careful, evidence-based, and rooted in both canonical procedure and pastoral responsibility.