On January 20, 2017, Elizabeth Lagesse stopped by a coffee shop in downtown Washington, DC, on her way to Donald Trump’s first inauguration as United States president.

The chemical engineering student had planned to join the protests taking place against his incoming administration.

But as soon as she walked out of the cafe, Lagesse found herself swept up in a police “kettle”, a controversial manoeuvre in which officers encircle crowds, preventing anyone from leaving. Lagesse was arrested along with dozens of others.

Some 234 people, including journalists, medics and legal observers, were ultimately arrested in Washington, DC, that day. All faced felony charges, including rioting and conspiracy to riot — serious crimes that carried the risk of decades in prison.

“I didn’t even get to do any protesting,” Lagesse told Al Jazeera. She spent more than a year fighting the charges. “It was 18 months of our lives and eight felony charges.”

Experts have argued that what happened was a startling example of government overreach, with historic implications for the right to free assembly under the First Amendment of the US Constitution.

Those implications, experts warn, resonate well into the present day, as Trump prepares to take office for a second term on Monday.

Police had clashed with a handful of protesters in the lead-up to the 2017 inauguration. With chants of “F*** Trump” and “Make racists afraid again”, several black-clad demonstrators smashed the windows of local businesses, including a bank. A limousine was set on fire. Officers responded with rubber bullets and tear gas.

But the government decided to charge nearly all the people arrested that day by advancing a unique argument: that all the protest participants — not just those who had carried out the vandalism — shared responsibility for supporting criminal conduct.

“It was a really shocking prosecution, and I don’t think people fully dealt with the potential ramifications of it,” said Chip Gibbons, the policy director at the free-speech group Defending Rights & Dissent.

“They brought really heavy-handed charges. It was really an abuse of the First Amendment.”