As if the Southern Poverty Law Center wasn’t already looking like a menace instead of a respected civil-rights outfit, now comes evidence that one of its top execs was sending donor cash to the white supremacist she was shacked up with.

To be fair, it’s long been obvious that the SPLC is a racket exploiting liberals (especially in the media) desperate for right-wing threats to condemn; the nonprofit raked in billions over the decades to support its (shoddy) research, including a “hate map” and database on supposed hate groups.

Now it stands charged with funneling funds to members of the Ku Klux Klan, neo-Nazis and other outfits it was raising cash to fight.

Its officers insist the payments were to “informants,” but the feds now say the “Director of the SPLC’s Intelligence Project” was “in a romantic relationship” with a member of the National Alliance — a white supremacist outfit — to whom she helped funnel $1.2 million in donor money.

Ick.

They allegedly even had a joint bank account to cover living expenses, so she profited from the payouts.

Per the SPLC’s own defense of its “informant” payoffs, the racist Romeo would raise money, induct new recruits and conduct “extremist activities” for the National Alliance, while copying documents to feed to his honeybunch handler, who then published SPLC reports on the inner workings of the hate group.

When the Alliance went on a leak hunt, the SPLC paid another informant to take the heat: How many of the haters weren’t on its payroll?

Yes, actual law-enforcement outfits sometimes use paid informants to help build criminal cases, but the SPLC is no such thing, and “sleeping with the enemy” is pretty much as compromised as any crusader can get.

What an embarrassment that the FBI and state law-enforcement agencies treated this outfit as a reliable source of information.

Again, that served the progressive cause, as the SPLC dutifully listed anodyne outfits like Moms for Liberty as extremists.

Such agitprop had ugly consequences: One lefty terrorist, relying on the SPLC database, in 2012 invaded the headquarters of the social-conservative Family Research Council looking to murder as many workers as possible, and actually shot a security guard.

There really are racists and Nazis in America, but the SPLC turned fighting them into a racket.

Beware: This is far from the only bunch of moralizers — all across the political spectrum — who are in bed with the evils they claim to combat.