It doesn’t get much richer than this: The state inspector general spent nine months “investigating” leaks out of the Joint Commission on Public Ethics — without ever even interviewing Gov. Andrew Cuomo or Assembly Speaker Carl Heastie, at least one of whom plainly received the illicit inside info.

We say “plainly” because the gov called the speaker to complain about how Heastie’s JCOPE appointees voted.

That vote was about whether JCOPE should look into the blatant violation by Cuomo’s 2015 campaign manager, Joe Percoco, who routinely did his political work out of his old state government desk — just steps away from the gov’s own office.

JCOPE only took up the question of a Percoco probe after the state GOP chairman sued to force a vote. And the info on the clear violation came up during the federal corruption trial that ended with Percoco sentenced to six years in prison back in 2016.

Yet a JCOPE probe of that campaign lawbreaking was evidently quashed. Worse, the quashing was plainly done at the direction of the governor — who was at the very least a bystander to the root wrongdoing.

Then the IG’s office found it “couldn’t” get to the bottom of the leak — when it obviously didn’t even try.

That pathetic “investigation” came after IG Letizia Tagliafierro recused herself from the probe — since she’s a Cuomo appointee and longtime loyalist. (She’s also a former JCOPE executive director.)

The bottom line: Every “ethics cop” in New York government is part of the problem, not the solution. That’s why corruption only gets uncovered when federal prosecutors get involved.