How loose are New York’s campaign finance laws? Well, the state Board of Elections is looking into whether a union’s political chief broke the letter or merely the spirit of the law by simultaneously serving as a party co-chairman.

The BOE has subpoenaed info on work done by Communication Workers of America District 1, a political action committee and super PAC it ran and three Democratic candidates in last year’s Senate races, reports the Albany Times Union.

The probe follows a complaint by state GOP chair Ed Cox over Bob Master’s role as both a key player at the union’s PACs and Working Families Party co-chairman.

State law lets party officials work with outside political groups if they don’t “coordinate” activity. But it’s hard to see how Master could have avoided such coordination.

At best, the maneuvering by multiple closely linked entities (the union, its PACs, the WFP and the candidates themselves) is a sneaky way around the laws, whose goal is to “level the field” on campaign donations and spending.

Consider: The groups were all pushing to topple Long Island Republican incumbent Sens. Kemp Hannon and Carl Marcellino. Master’s WFP endorsed their opponents, while his CWA super PAC spent more than $770,000 on Senate races.

Of course, these are hardly the only laws New York insiders game. As Citizens Union notes, 30 percent of today’s state lawmakers were handed their jobs by party bosses, who tapped them as the only candidate in a special election or when a seat opened up after the filing deadline to get on the ballot the normal way.

Meaning none had to compete in a primary. And with so many New York districts dominated by one party, that generally guarantees you an easy ride into office.

Want more sleaze? Keith Wright, who won re-election Saturday as the Dems’ Manhattan boss, is now overseeing the process to fill two such vacancies. Yet he’s a key player at a lobbying firm that will be dealing with the lucky winners.

It’s getting tough to find ways in which New York politics isn’t rigged.