VANCOUVER, B.C. - The senior Mountie who was in charge of the investigation into Robert Dziekanski's death says the national police force shouldn't investigate itself.

Supt. Wayne Rideout was in charge of criminal operations in the region and headed the investigation into Dziekanski's death in October 2007, after four RCMP officers stunned him with a Taser at Vancouver's airport.

The resulting investigation has been the subject of intense public scrutiny and even allegations of a coverup.

Rideout maintains there was nothing wrong with the investigation, but he says bringing in an outside body would avoid the sort of public perception problems that have plagued the Dziekanski case.

Just last month, the RCMP's federal watchdog also said the force shouldn't investigate itself, although the RCMP has resisted turning over such cases to outside bodies.

The inquiry resumed Tuesday to hear from senior Mounties about an internal RCMP email that seemed to suggest the officers planned to use a Taser before they ever set eyes on Dziekanski.