(NewsNation) — A former member of the Oath Keepers called the decision by a jury Tuesday to convict the founder of the group with sedition crimes “necessary” and warned about the potential for future violence in the next two years.

Stewart Rhodes was found guilty of seditious conspiracy after a nearly two-month-long trial that showcased the far-right extremist group’s efforts to keep Republican Donald Trump in the White House at all costs. Prosecutor argued Rhodes was the mastermind behind a violent plot to overthrow Joe Biden’s presidential win during the Jan. 6, 2021, riots at the U.S. Capitol.

Using dozens of encrypted messages, recordings and surveillance video, prosecutors made the case that Rhodes began shortly after the 2020 election to prepare an armed rebellion to stop the transfer of presidential power.

Over seven weeks of testimony, jurors heard how Rhodes rallied his followers to fight to defend Trump, discussed the prospect of a “bloody” civil war and warned the Oath Keepers may have to “rise up in insurrection” to defeat Biden if Trump didn’t act.

Jason Van Tatenhove, a former Oath Keepers member, testified to Congress earlier this year about Rhodes and the group, which Van Tatenhove left years ago. Tatenhove said Tuesday on “CUOMO” that the conviction was necessary.

“We needed to show some actual repercussions for the leadership of these types of organizations,” Van Tatenhove said. “We’ve seen a ratcheting up of these incidents, events, standoffs, where it has become more and more extreme from Bundy Ranch on through Jan. 6.”

Van Tatenhove, a former spokesman for the group, told the Jan. 6 House committee he had grown concerned about an embrace for white nationalists and finally left the group after hearing senior Oath Keepers deny the Holocaust. During the hearing, he said words and tweets by Trump essentially “gave the nod” to Rhodes that it was time for action.

“They had the ear of a sitting president at one point,” Van Tatenhove said.

Defense attorneys accused prosecutors of twisting their clients’ words and insisted the Oath Keepers came to Washington only to provide security for figures such as Roger Stone, a longtime Trump ally. The defense focused heavily on seeking to show that Rhodes’ rhetoric was just bluster and that the Oath Keepers had no plan before Jan. 6 to attack the Capitol.

Rhodes testified that he had no idea that his followers were going to join the mob and storm the Capitol and said he was upset after he found out that some did. Rhodes said they were acting “stupid” and outside their mission for the day.

Even though Rhodes faces up to 20 years in prison Van Tatenhove said the Oath Keepers won’t just cease to exist. He theorized a power vacuum will emerge, creating problems of its own.

“Stewart Rhodes was a known quality, he was kind of the devil we knew. He always kind of toed that legal line,” Van Tatenhove said. “It may be a different story entirely if we have someone else that rises up to fill that leadership vacuum that’s willing to lead the charge into something like a January 6th event. Right now we have to consider and be diligently at watching what manifests in that vacuum that’s left.”

The Associated Press contributed to this report.