Opinion

A crook as comptroller?

City Comptroller John Liu has a secret about his campaign cash — and it looks like it’ll take a district attorney to get him to come clean.

Paging Manhattan DA Cyrus Vance . . .

Clearly, the need for an official, all-out probe of Liu’s campaign-funding hanky-panky — by a prosecutor with full subpoena power — grows more compelling with each passing day.

The latest? Liu’s backtrack on his promise to disclose the names of his cash bundlers.

After a recent New York Times investigation raised serious questions about the veracity of his campaign donor list — and the legality of individual gifts — Liu offered to make public the names of folks who’ve solicited money for him.

A magnanimous act?

Not quite: Candidates are actually required to do so by campaign-finance rules.

And yet on Thursday, the Times reported that Liu & Co. had a sudden change of heart: No names would be released until at least after the next campaign-finance filing deadline in January. (If ever.)

Liu’s campaign lawyer, Martin Connor, claimed the new decision was based on advice from the city’s Campaign Finance Board — but a CFB official denied ever having given such advice.

You wondering what we are? What’s Liu trying to hide?

Actually, though, whether the comptroller — the man New Yorkers trust to watch over their tax dollars — is open and honest with them going forward isn’t nearly as critical as whether he’s already broken the law.

That is, Liu’s expected 2013 mayoral race can’t be the focal point — but rather his 2009 comptroller’s run.

Did he get taxpayer funds under fraudulent pretenses?

Based on what’s known publicly, the answer appears to be yes.

Remember, for every dollar Liu claims to have raised from legitimate private sources, his campaign got up to six bucks in city funding — under campaign-finance rules.

But dozens of supposed donors say they never actually gave him any dough.

Some 18 construction workers were listed as having given him $800 each (eight is a lucky number in China) — but handwriting on their donation cards suggests the money came from a single source, possibly allowing a real donor to skirt legal limits.

Other possible violations abound.

So, to repeat: If a candidate takes public money based on fraudulent claims, a crime has been committed.

Ex-City Councilman Sheldon Leffler actually went to jail for using different names to mask an illegal $10,000 contribution from a single donor.

Liu can’t credibly do the job he has now with this cloud hanging over him.

Vance needs to sort it out.

Now.