Most New Yorkers don’t know who their state legislators are or what they do (or don’t do).

But there’s no better illustration as to why they should than the impending debacle over rent regulations in New York City.

Last year the Democrats had their best shot at strengthening rent regulations and lifting the threshold for vacancy decontrol above the $2,000 it was set at in 1994.

But one of the Democrats was Pedro Espada, who fashioned himself a man of the people but preferred to live in the Westchester suburb of Mamaroneck while he fashioned sham pro-tenant legislation that was designed to favor his benefactors in the real estate industry. In nabbing the chairmanship of the Housing Committee by holding the evenly split Senate hostage, he was able to block key tenant bills at will.

Voters had the good sense to remove Espada for this and a variety of alleged transgressions, but we are still left with his “amigo,” Bronx State Senator Ruben Diaz, Sr., an Espada enabler who voted in favor of the so-called “Rent Freeze” bill but now has amnesia.

A couple of weeks ago, Diaz beat up on Mayor Bloomberg and Council Speaker Christine Quinn for their push for gay marriage legislation; he said they should be focused on the Emergency Tenant Protection Act.

Surprised by Diaz’s sudden concern for tenants, we asked him why he sided with Espada last year on a bill that would have undermined rent stabilization.

“I don’t even know what you’re talking about,” he said. “This is this year. That was last year.”

When he was reminded of his vote, and that he attended Espada’s rally for the bill, he said it was in the name of friendship.

Bronx tenants don’t need their elected legislators to be “friends.” They need them to do the people’s business, which would have been to stand up to Espada last year.  This year, strengthening rent laws beyond a simple renewal of weak regulations has little chance of passage because of the

Republican takeover of the Senate, so Diaz’s conversion serves only himself.

Diaz may have forgotten what he did to jeopardize the living situations of thousands of Bronxites, but his constituents never should.