OTTAWA - Prime Minister Stephen Harper has named an interim ethics commissioner in the wake of Bernard Shapiro's unexpected resignation last week.

Robert Benson, who has been serving as deputy commissioner, will take the top job until the government nominates a new commissioner for formal consideration by the House of Commons.

Benson is a government lawyer who was named deputy commissioner when the ethics czar's office was set up by then-prime minister Paul Martin in May 2004.

Before that, Benson was with the RCMP external review committee and also worked with the Justice Department.

Shapiro, a former president of McGill University, gave no reasons for his resignation last week.

During his tenure, Shapiro ran afoul of politicians of all stripes.

The NDP tried to oust him and Harper refused to co-operate with one of his investigations.

Harper has offered a formal thank you to Shapiro for his services.