OTTAWA _ There was no top-level interference in the police probe that led to criminal charges against former privacy commissioner George Radwanski , says the Mountie who headed the investigation.

Radwanski has voiced concern that the RCMP investigation may have been tainted by previous run-ins he had on a variety of policy issues with then-RCMP commissioner Giuliano Zaccardelli.

But Supt. Al Mathews, testifying Tuesday in Ontario Superior Court, said Zaccardelli never spoke to him nor issued any directives about how to handle the politically volatile case.

``The responsibility for operating the file was mine,'' said Mathews. ``Had there been any direction by the commissioner, we would have been very concerned (but) it never came up at all.''

Mathews acknowledged the investigative team did periodically brief the economic crime branch at RCMP headquarters. But he said that was standard procedure in any ``sensitive'' case and was intended merely to keep supervisors apprised of their progress.

Radwanski, who quit the privacy post under fire in 2003, now faces charges of fraud and breach of trust related to expense claims he filed while in office.

His lawyer, Michael Crystal, says the Mounties should have bowed out and handed the matter over to another police force because of a potential conflict of interest.

Crystal also contends the RCMP seized material from Radwanski's former office without a search warrant, and he argues the evidence should be set aside and not used in any future trial.

Mathews, who holds a law degree, replied Tuesday that the material was voluntarily handed over by Robert Marleau, who served as Radwanski's interim successor as privacy commissioner.

The Mounties considered that arrangement to be legally permissible because the commissioner's office had been the theoretical ``victim'' of any purported fraud committed against the government.

The RCMP is not the only organization accused by Radwanski of treating him unfairly.

He also contends he was denied procedural fairness by Auditor General Sheila Fraser's staff during their own investigation of the affair. Defence lawyer Crystal has filed a motion asking that the charges against his client be stayed because of their actions. © 2008 The Canadian Press