With a labour relations board decision in June, the Canada Revenue Agency took another step toward parting ways with the same employee for the third time in more than 15 years.

That employee, Mohammed Tibilla, is a former CRA worker based in Montreal. Over the years, he has launched administrative or legal actions and filed appeals against the agency, his union and his supervisors numerous times, exposing weak spots in federal systems — and underscoring the challenges Prime Minister Mark Carney faces in trying to make the government more streamlined and responsive.