(AP) — Four members of anti-government groups are facing trial this week on federal charges accusing them in a chilling plot to abduct Michigan’s Democratic governor, Gretchen Whitmer, in 2020.

Jury selection begins Tuesday in a trial that could last more than a month in federal court in Grand Rapids, Michigan.

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Here’s a look at the charges and what’s required to secure convictions:

WHO ARE THE DEFENDANTS?

Six men were initially charged but two pleaded guilty before trial.

The remaining defendants include Adam Fox, described by prosecutors as the plot’s ringleader. He and co-defendant Barry Croft Jr. were affiliated with the “Three Percenter” far-right anti-government movement. Prosecutors say the other two defendants, Daniel Harris and Brandon Caserta, were members of the Wolverine Watchmen, a self-styled militia with similar views.

Ty Garbin pleaded guilty last year and Kaleb Franks joined him in February. Both are expected to be star government witnesses.

WHAT ARE THE CHARGES?

All four are charged with kidnapping conspiracy.

Charging documents say the defendants plotted from June to October 2020 to grab Whitmer at her vacation home because they were infuriated by what they saw as her overly restrictive policies during the pandemic.

Fox, Croft and Harris are also charged with conspiracy to use a weapon of mass destruction. The indictment says they sought to construct and buy explosives, including to destroy a bridge near Whitmer’s cottage during the kidnapping.

Croft and Harris are also accused of possession of an unregistered destructive device, a firearm.

Harris is charged with possession of a semiautomatic assault rifle with a barrel less than 16 inches long that wasn’t registered to him.

WHAT ARE THE POTENTIAL SENTENCES?

If convicted, all four could face the prospect of spending the rest of their lives behind bars.

The kidnapping conspiracy and conspiracy to use a weapon of mass destruction charges each carry a maximum life sentence.

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The maximum sentence for possession of an unregistered destructive device is 10 years, and Harris could face up to three years in prison if convicted of the semiautomatic rifle charge.

Garbin has already been sentenced to six years in prison, and Franks is also likely to receive a lighter sentence than if he had lost at trial.

WHAT’S REQUIRED TO SECURE CONVICTIONS?

The defendants never achieved their purported goal of kidnapping Whitmer. Unbeknownst to them, the FBI had infiltrated their group and was closely monitoring them. They were arrested in October 2020.

The trial’s focus will be on whether the plot was more than idle talk of wannabe weekend warriors. To prove it was deadly serious, prosecutors will seek to show how defendants took specific steps, referred to as “overt acts” in the indictment, toward implementing their plans.

Jury instructions proposed by prosecutors prior to trial explain that convictions on the kidnapping and weapons conspiracy charges require evidence that each defendant committed at least one of the long list of overt acts in the indictment.

“This is essential,” the filing says.

It adds that “proof a defendant simply knew about a conspiracy … or associated with members of the group, is not enough (for a conviction), even if he approved of what was happening or did not object to it.”

Proving a conspiracy doesn’t require a written or even a spoken agreement among conspirators, the filing explains. A mutual understanding — spoken or unspoken — can suffice.

The weapons charges are more straightforward. Prosecutors only have to have to show the weapons were in a defendant’s possession and not legally registered.

WHAT ARE THE ALLEGED OVERT ACTS?

Among 19 acts listed under the kidnapping conspiracy count is that Fox proposed the kidnapping of Whitmer on Aug. 23, 2020, during a meeting with Harris and Caserta. During the gathering, they also scrutinized each other’s IDs in a bid to ensure no one was an undercover agent, the indictment says.

The indictment says Fox, Croft, Harris and Caserta held field-training exercises in September 2020, practicing tactics for fighting Whitmer’s security detail. The indictment says Croft and Harris tested explosives, hanging human silhouette targets to demonstrate the spread and reach of the shrapnel.

The indictment attributes another overt act on Oct. 7, 2020, to Caserta, alleging he instructed co-conspirators that, if they encountered police, they should give the officers one chance to leave, then kill them if they didn’t.

Among 27 overt acts prosecutors listed under the weapons of mass destruction charge is that Harris boasted on May 1, 2020, that he was a Marine Corps veteran who “can make things go boom if you give me what I need.”

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