Metro

The biggest Liu-ser!

City Comptroller and mayor wannabe John Liu has lost his challenge to the biggest campaign-poster fine ever meted out in the Big Apple, according to records released yesterday.

Only three days ago, Liu announced he had hired a respected former attorney general to audit his own campaign books amid questions about his campaign-finance reporting.

According to an Oct. 20 ruling, the city Office of Administrative Trials and Hearings upheld $527,400 in fines against Liu’s 2009 comptroller’s campaign for hanging political posters on public land — including utility poles.

“We are pleased that [the decision] upholds our original actions,” said spokesman Vito Turso of the Sanitation Department, which issued the violations.

The ruling marked the second time the Sanitation Department and the comptroller did battle over the posters used by Liu’s first citywide campaign. The first round of fines were thrown out on technical grounds, only to be refiled by Sanitation officials.

The new judgment was based again on technical grounds: Liu’s campaign did not contest the fines. Instead, the comptroller’s lawyers argued that the violations were served on a former campaign official who was not authorized to receive them.

Administrative Law Judge Nancy Gold disagreed with Liu’s position, sustaining the violations.

Liu’s attorney Martin Connor said the ruling is not the end.

“We respectfully disagree with the decision and we intend to appeal,” Connor told The Post.

If ultimately upheld, the fines could grow to include interest payments on top of the original penalty amounts.

As Liu continues to fight his fines, Public Advocate Bill de Blasio, one of the other contenders for the 2013 Democratic nomination for mayor, has given up his battle.

The Post reported exclusively last month that de Blasio, after more than two years, agreed to pay $300,000 plus interest for poster violations also accumulated during the ’09 campaign season.

Liu has been struggling through a spate of some bad publicity of late, culminating last Friday in the announcement that he had retained former state Attorney General Robert Abrams to audit his campaign’s financial records.