Democrats’ strategy for the Senate impeachment trial is apparently to turn it into a never-ending Senate investigation — even though that was supposed to be the House’s job.

Start with the General Accounting Office opinion that Team Trump’s temporary hold on aid to Ukraine constitutes a violation of the law. Maybe — but the GAO is no kind of court or other legal authority. If this was a real issue, the House could’ve raised it long ago. “We forgot” is just an old Steve Martin joke.

Then there’s the claim that assertions by Rudy Giuliani crony — well, ex-crony — Lev Parnas just plain compel the Senate to consider “new evidence” and call witnesses to get to the bottom of the Ukraine affair.

Rudy looks pretty foolish, and sleazy, for ever associating with this guy. But Parnas is facing federal indictments and plainly figures his best bet to skip prison is to win an immunity deal by confirming every conceivable anti-Trump suspicion. His “evidence” is mainly his own handwritten notes — written when? Can he prove that?

All this is starting to seem like a farcical replay of the Brett Kavanaugh confirmation hearings, which had wrapped up until Democrats decided to play the Christine Blasey Ford card. That prompted a media furor that led to excruciating extra hearings, which changed no one’s mind. Then they pushed for more hearings about other, even less substantial charges. Even the now-disgraced Michael Avenatti got into the act.

The House is supposed to finish its investigation before sending the case to the Senate — not demand the Senate do the real work. What’s to prevent Adam Schiff & Co. from coming up with more Parnases (and Avenattis) to stretch this out for months?

As former federal prosecutor Andy McCarthy notes, a regular court facing this sort of stunt would stop the trial until the prosecution actually finished its investigation.

Two months ago, Democrats insisted the president was such a danger to the country that they didn’t dare take time to build a stronger case. Now they’re eager to keep the case going … forever: Just keep building up ever more fog.

As a bonus, the strategy leaves the Senate unable to do any other work, such as confirming more judges. It also keeps Chief Justice John Roberts from doing his normal work at the Supreme Court.

The Senate must reject Democrats’ “endless overtime” approach. Either send the articles of impeachment back to the House, marked “incomplete,” or just move straight to a final vote after the opening arguments.