An Ontario Superior Court judge is telling federal tax authorities they can't set limits on how much a charity devotes to political activity in a new ruling that grants a win to a national anti-poverty group.

Justice Ed Morgan said in the decision Tuesday that the Canada Revenue Agency could not justify a restriction on charities that they spend no more than 10 per cent of their time on political advocacy, calling it an unconstitutional limit on freedom of expression.

Morgan's ruling — which begins with the philosophical question, what is political? — says all political activities are charitable activities so long as groups advocate "in pursuit of the overall charitable purpose."