OTTAWA -- Treasury Board President Tony Clement says concerns over a Conservative move to retroactively rewrite the law in order to stop an investigation of alleged RCMP wrongdoing are akin to angels dancing on the head of a pin.

The latest omnibus budget bill from the Harper government quietly inserted amendments, backdated to October 2011, that wipe clean any complaints about the handling of long-gun registry data before Parliament passed a bill to end the registry the following year.

Clement says that since Parliament did eventually pass a law to end the registry, complaints about when that law took effect are simply arcane legal nitpicking.

Federal information commissioner Suzanne Legault issued a special report last week calling the move a "perilous precedent" that could be used to retroactively clear government officials of wrongdoing on everything from election fraud to spending scandals.

She recommended to the attorney general of Canada in March that an investigation be launched into the RCMP's wilful destruction of registry data that was covered by the Access to Information Act -- an investigation that has now been taken on by the Ontario Provincial Police.

The Harper government responded by retroactively rewriting the law, backdating the amendments to the day the bill to end the long-gun registry was first introduced in Parliament, and then burying the changes this month in a 167-page budget bill that will be rammed through Parliament before the summer recess.

Clement, whose portfolio includes overseeing and enforcing Canada's access-to-information law, brushed off Legault's concerns about a future government using the same after-the-fact tactic to clear itself in the face of an active police investigation.

"I don't think it sets any precedent at all," Clement said Wednesday following a Conservative caucus meeting.

"Lookit, Parliament passed a law. The law that was passed by Parliament was no more long-gun registry."

Reporters then pointed out that the new amendments will rewrite history to put the gun registry data destruction law into effect long before it was voted on by Parliament.

"You know, now we're getting into angels dancing on the head of a pin, which lawyers are very good at and Ms. Legault is a lawyer," Clement responded.

"But the law of the land is that registry should not exist anymore."

Legal and parliamentary procedure experts say the Conservative move is unprecedented but that it cannot be stopped under a majority government. The Treasury Board president agreed.

"The sovereignty of Parliament I think trumps in this case," said Clement.