Someone should tell David Shearer that getting all indignant about someone else's blunder was not the best of tactics to employ in Parliament yesterday, given that little over a week ago he fessed up to making a rather large blue himself.
Listing an alphabet soup-load of Government entities guilty of similarly serious breaches of privacy - the ACC, MSD and the IRD - the Labour leader wanted to know what the Prime Minister was doing to avoid a repeat of the latest lapse at the Earthquake Commission.
Unable to control his beaming smile, John Key replied that people made mistakes.
Was Shearer saying the staff member at fault at the commission should be sacked? If so, that was a pretty high standard to meet - and one that Shearer had himself failed to meet.
Key was referring to Shearer's strange memory lapse which resulted in him failing to include a $50,000-plus New York bank account in the MPs' register of pecuniary interests.
Shearer persisted, asking Key why it had not been made mandatory for all Government agencies to use secure email technology which was designed to protect data when sending attachments.
For Key, it was like shooting fish in a barrel. As the questions continued, Key managed to squeeze in further references to Shearer's embarrassment - much to the annoyance of the latter's colleagues who rounded on Speaker David Carter for allowing Key to continue to insert what was irrelevant material into his answers.
Labour strategists would argue Shearer had little choice but to go head-to-head with the prime minister on the issue of the day. Otherwise, he would have suffered a monumental loss of face.
The alternative was for Shearer to lead Labour's attack on yesterday's job cuts in the financially-stretched Department of Conservation.
Even here Shearer was not safe. When Labour front-bencher Jacinda Ardern questioned whether Conservation Minister Nick Smith would guarantee the endangered black petrel would not become extinct because of the cuts, the minister quick as a flash replied that he rated the chances of the black petrel surviving as far greater than those of the Leader of the Opposition.
Smith was certainly in the mood for a flutter.
When Labour's Damien O'Connor suggested DoC's Takaka office would be reduced to one staff member, Smith said he would be happy to have a bet with the Opposition MP for the best bottle of Nelson wine that following the restructuring there would be more staff in Takaka than just one.
O'Connor restored some honour for Labour, however. He noted Smith had made the same bet over the effect on prices of National's electricity reforms. "I am still waiting for the bottle of wine."