Federal prosecutors announced Friday that they will drop all charges against activists arrested and accused of rioting during President Trump's inauguration.

The decision follows two unsuccessful trials in which jurors either acquitted or deadlocked on charges against members of a largely black-clad anti-capitalism march. Other cases were dropped after a judge found prosecutors improperly withheld evidence.

"In light of the results in the cases brought to trial... the U.S. Attorney’s Office has now moved to dismiss charges against the 39 remaining defendants in this matter," office spokesman Bill Miller said in an afternoon statement.

The statement does not address the alleged withholding of video evidence from defense attorneys. Prosecutors allegedly failed to inform defendants about voluminous Project Veritas footage, some of which cast doubt on allegations of shared planning.

More than 230 people were mass-arrested north of Trump's inaugural parade route after some members of the march vandalized storefronts and vehicles, leading to a police chase through downtown Washington that featured generous use of pepper spray and batons.

Prosecutors sought to force plea deals through use of tough felony charges that by statute could have brought more than 70 years in prison. Twenty people pleaded guilty to a single misdemeanor count of rioting in exchange for a year on probation.

The dismissal of the charges likely helps civil litigation against the authorities based on allegations of false arrest and police brutality.

A case on behalf of six people was filed by the local chapter of the American Civil Liberties Union, alleging some clients were subjected to cavity searches from laughing police officers who didn't change gloves between inspections.

Another lawsuit seeking class-action certification was filed by D.C. attorney Jeffrey Light. Attorneys in both civil cases are currently fighting government motions to dismiss.

Light and ACLU attorney Scott Michelman told the Washington Examiner that dismissal of charges could strengthens arguments around false arrest.

"Law enforcement's handling of the demonstrations on Jan. 20 has been bungled from the start — it was guilt by association policing, and guilt by association prosecution," Michelman said.

Michelman noted that an officer wearing a T-shirt to court during the second trial that said "Police brutality... or doing what their parents should have?" indicates a worrying mentality celebrating police misconduct.

Light said it was "way too early" to discuss potential settlement amounts per activist. A series of lawsuits following a D.C. mass-arrest during World Bank protests in 2002 resulting in widely varying settlement amounts, totaling an estimated $17 million.

The failure of the inauguration trials came in two distinct waves.

At an initial trial last year, prosecutors argued that by merely attending the march, six people were guilty of five felony counts of property destruction and three counts of rioting. Prosecutors conceded there was no evidence they personally committed an act of violence or vandalism, but likened the larger march to a "getaway car," facilitating those who did.

Jurors rejected the argument. One juror told the Washington Examiner afterward that "the jury as a whole believes it's a legal act to attend a protest where vandalism occurs." Prosecutors subsequently dropped charges against 129 other defendants.

Last month, the second rioting trial against four defendants resulted in an acquittal for a man accused only of knowledge of protest planning, and deadlocked decisions against three other men, resulting in mistrials. A juror note to the judge revealed that the jury had a group conversation about the concept of jury nullification after one member read "Google jury nullification" on a bathroom stall and decided to do so.

Separately, prosecutors faced accusations of withholding Project Veritas footage. Judge Robert Morin, ruling on pretrial motions for 10 defendants, dismissed seven cases and reduced three others in late May after finding prosecutors improperly concealed videos, ruling that "it’s a serious violation" of their rights.

"The U.S. Attorney's Office and D.C. police spent virtually a blank check of taxpayer dollars in an outrageous prosecution of hundreds of people for being in proximity to, or participating in, First Amendment activity," said Mara Verheyden-Hilliard of the Partnership for Civil Justice Fund, which is suing for more information on police links to Project Veritas.

"While upending people's lives who've had to defend themselves, they failed to convict anyone at trial," she added. "They've been exposed as partnering with the right-wing political opponents of anti-Trump protesters. They've been exposed for doctoring and withholding evidence from the defense. It's time to investigate the U.S. Attorney's Office and the [Metropolitan Police Department] for their outrageous actions in this matter."

Prosecutors stood by their decision to prosecute the group, even in announcing the decision to drop all remaining charges.

"The U.S. Attorney’s Office for the District of Columbia believes that the evidence shows that a riot occurred on January 20, 2017, during which more than $100,000 in damage was caused to numerous public and private properties," Miller said in his statement. "The destruction that occurred during these criminal acts was in sharp contrast to the peaceful demonstrations and gatherings that took place over the Inauguration weekend in the District of Columbia, and created a danger for all who were nearby."