Craig 'Craig Thomson' Thomson

Image © 2011 AAP One / Lukas Coch

Workplace Relations Minister Bill Shorten says as far as he knows no one in the federal government has interfered in a Fair Work Australia (FWA) investigation involving a Labor MP.

The agency is nearing the end of a long investigation surrounding allegations of misuse of a union credit card by Labor backbencher Craig Thomson when he was national secretary of the Health Services Union (HSU).

Its formal investigation has been running since March 2010, although the allegations were first raised in April 2009.

Current HSU national secretary Kathy Jackson says there needs to be an external inquiry into why the investigation is taking so long and she could not rule out interference by the government.

Mr Shorten rejected any allegations of government interference.

"To my knowledge they haven't interfered, no," he told ABC Radio on Wednesday.

Mr Shorten said FWA had indicated its report of the investigation would be released on or around March 5.

Cabinet secretary Mark Dreyfus said Ms Jackson herself had said she had no evidence for her allegations.

"People should lay off independent public servants that are going about their job," he told Sky News.

"This is an independent statutory agency and when it's finished its investigation and made its report public, that's the time for comment on it."

Liberal Party backbencher Jamie Briggs said Ms Jackson was just "truth-telling".

"It's some pretty hard questions for the prime minister to answer today," he said.

For more on this story, we’ll be crossing live to Kathy Jackson on the Project tonight.

AAP

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