An Alberta widow will be allowed to keep tens of thousands of dollars her late husband left to her in retirement savings after winning a years-long court battle against the Canada Revenue Agency.

The ruling Tuesday said Marlene Enns is exempt from a clause in Canadian tax law that gives the tax agency power to collect unpaid tax debts from spouses or common-law partners in certain cases because, under law, her marriage ended the moment her husband died.

The appeal court ruling settles a question that for years did not have a clear answer, after other cases involving widows in the Tax Court of Canada ended with conflicting answers: what should the definition of “spouse” be in cases like the one involving Enns.