The head of the Secret Service managed to do something this week on Capitol Hill that few people ever achieve before the Congress.

Kimberly Cheatle provided such useless public testimony Monday about the July 13 assassination attempt against Donald Trump that lawmakers immediately joined across party lines to demand her resignation, which came a day later.

“It’s only the beginning of the accountability we must see from the U.S. Secret Service,” said U.S. Rep. Barry Loudermilk, R-Cassville, as frustrated Republicans demanded to know how a gunman could get on a roof with an AR-15-style rifle and almost kill the former president at a rally in Pennsylvania.

A witness trying to stonewall lawmakers at a congressional hearing is nothing new. But what we saw from Cheatle was next-level stuff for a top government official.

“Do you have a timeline — at all — from any of the day,” asked U.S. Rep. Marjorie Taylor Greene, R-Rome, at one point.

“I have a timeline that does not have specifics,” Cheatle answered. Greene later accused her of a cover-up.

If Cheatle thought that Democrats would run interference for her, she was sorely mistaken.

“I left that meeting feeling like it was all secret and no service,” quipped U.S. Rep. Jamie Raskin, D-Md., who immediately called for Cheatle to resign.

Cheatle, who served for 27 years as a Secret Service agent, including a stint as the head of the Atlanta field office, properly described the attack at the Trump rally as “the most significant operational failure at the Secret Service in decades,” the worst since President Ronald Reagan was shot outside a Washington hotel in 1981.

But Cheatle’s nonanswers helped drive the two parties together in a highly unusual way during an election year, as House leaders agreed to set up a special 13-member task force to investigate the Trump assassination attempt.

“We need to get the answers that the American people deserve,” House Speaker Mike Johnson said.

“We need a committee solely focused on what the specific failures were and how we fix them,” said U.S. Rep. Jared Moskowitz, D-Fla.

Two days after Cheatle’s disastrous appearance before Congress, FBI Director Christopher Wray took a completely different approach, repeatedly offering and volunteering information about his agency’s investigation.

Even so, Wray acknowledged that the reason for the shooter’s attack remained unclear.

“We do not yet have a clear picture of his motive,” Wray told a House committee Wednesday.

Wray had the much easier job of rattling off details about the investigation. The Secret Service has a much more difficult review of the mistakes made on the day of the attack.

Those specifics could well prove embarrassing. But not providing details — or just stonewalling the Congress — isn’t the answer.

Jamie Dupree has covered national politics and Congress from Washington since the Reagan administration. His column appears weekly in The Atlanta Journal-Constitution. For more, check out his Capitol Hill newsletter at http://jamiedupree.substack.com.