A Montco man said he rescued a woman from Capitol rioters on Jan. 6. Video shows him punching a cop in the head.

Jim Robinson, of Schwenksville, told a federal judge last year he’d entered the U.S. Capitol on Jan. 6, 2021, only to help people in distress — including a 60-year-old woman he says he rescued from nearly being trampled by the mob that had stormed the building.

Newly discovered surveillance footage says otherwise, prosecutors said, as the 61-year-old martial arts instructor was sentenced Tuesday to six months in prison.

The video, Assistant U.S. Attorney Michael Lawrence Jones told the court, offers no evidence to support Robinson’s contention that he helped anyone. Nor does it show him, as he’s also claimed, stopping other rioters from throwing a bucket of paint or from smashing statues in the Capitol Rotunda.

In fact, the prosecutor said, it shows Robinson at the forefront of the crowd, pumping his fist and chanting, with a velvet rope stolen from a security stanchion draped over his shoulder like a trophy.

And that all comes before the part where Robinson is caught on tape punching a police officer in the head — an act he followed, after he was finally pushed out of the building, by lingering on the Capitol steps and belting “Proud to be and American” as he raised his arms in victory.

U.S. District Judge Dabney L. Friedrich cited all of that during Robinson’s sentencing Tuesday as she imposed the maximum sentence allowable under the misdemeanor count of disorderly conduct on Capitol grounds to which he pleaded guilty earlier this year. She also ordered him to pay $1,500 in restitution and fines.

But prosecutors noted that had the footage of his assault on officers surfaced earlier, it’s almost certain Robinson would have been charged with felony crimes — and facing much more serious time. His punishment, Jones wrote in court filings, is “still the lightest sentence any January 6 defendant has received who punched a police officer.”

Robinson’s case is hardly the first instance of a Capitol rioter dodging serious charges due to the late discovery of crucial evidence as investigators pore over the thousands of hours of surveillance footage and social media videos as part of what the U.S. Justice Department has described as the largest investigation in its history.

Last month, prosecutors confronted Zach Rehl — the former president of the Philadelphia chapter of the Proud Boys — as he testified in his own defense at a sedition trial with newly surfaced police body cam footage that appeared to show him pepper-spraying officers. He hadn’t previously been accused of attacking cops.

» READ MORE: Proud Boys trial: Zach Rehl, the right-wing group’s Philly leader, and three others convicted in Jan. 6 sedition case

But the case of Robinson — known to his students as “Master J” and former owner of the now-defunct King of Prussia-based Robinson’s Martial Arts & Fitness — stands out for significant disparities between the role he described playing in the riot when he was charged and pleaded guilty to a misdemeanor in February and the conduct for which he was ultimately sentenced Tuesday.

In his telling, he entered the Capitol as a hero.

A fourth-degree master black belt in the Korean fighting style of Tang Soo Do, he said he’d always been taught to help people in need and had rushed into the fray on Jan. 6 by screams and cries of people in distress.

In addition to the 60-year-old woman he claimed to have rescued, he said he’d chided another rioter for lighting up a joint in the Capitol Rotunda.

“No matter what side or what beliefs you have, that’s not what you do in the building,” he told Friedrich at his guilty plea hearing earlier this year.

But his respect for the sanctity of the halls of U.S. government apparently did not extend to those charged with protecting it.

In the footage shown to the court Tuesday, he could be seen swatting at and pushing an officer who attempted to remove him from the Capitol Rotunda. When the officer raised his baton, Robinson balled his hand into a fist and punched.

It wasn’t the only instance during Tuesday’s sentencing hearing of Robinson’s version of events falling short of the full truth.

In filings leading up to the proceeding, his attorney Allen Howard Orenberg maintained Robinson doesn’t subscribe to any “far-right political views.”

“He has been the subject of a number of media accounts lumping him in with others that were there on January 6,” Orenberg wrote.

But Robinson’s social media, littered with images of him in various martial-arts posts, feature one photo of him holding an American flag with the logo of the antigovernment militia the Three Percenters. Other posts are peppered with right-wing messages railing against everything from inflation to COVID-19 precautions and vaccines.

Orenberg also described his client expressing “sincere and complete remorse.”

But an online fundraising site launched to pay for his legal defense on GiveSendGo, a website popular among right-wing figures and Jan. 6 defendants, indicates otherwise.

“Their goal is to harass conservatives,” the pitch for $20,000 in contributions reads. His prosecution “may bankrupt Jim.”

As of Tuesday, it had raised $930.