State Sen. Justin Eichorn, R-Grand Rapids, resigned his seat Thursday amid allegations that he solicited sex from a minor.

Eichorn submitted his letter of resignation to Gov. Tim Walz just before the Senate was set to take up a motion to expel him.

“I am resigning my seat in the Minnesota Senate for District 6 effective immediately,” Eichorn wrote. “I must focus on personal matters at this time. It has been an honor to serve in the Minnesota Senate.”

Eichorn also made an appearance in federal court on Thursday, where he was ordered to remain in custody until a bed opens up in a halfway house. He will also only be able to see people under the age of 18 — including his own children — when supervised by the court.

Eichorn’s Republican colleagues stated Wednesday evening they would move to have him expelled, and the DFL Senate caucus voiced its support for the measure Thursday morning.

An expulsion would have been a first for the Minnesota Senate, but Eichorn’s resignation removed the need for such a vote.

“This is the right thing to do for his family and the Senate. We are ready to move on and do the important work that needs to be done at the Capitol,” said Senate Minority Leader Mark Johnson, R-East Grand Forks.

After Eichorn was formally charged with soliciting a minor for prostitution on Wednesday, the governor called for his resignation.

“You cannot prey on our children and think you’re going to get away from it — that’s a big deal,” Walz said during a news conference.

Investigators say Eichorn tried to hire someone he thought was 17 for sex. A federal criminal complaint says he responded to an ad posted by undercover law enforcement as part of a sex trafficking operation earlier this month.

Eichorn was arrested Monday evening after he allegedly arranged to meet with an undercover Bloomington Police Department officer who was posing as a 17-year-old girl.

Charging documents indicate Eichorn was familiar with industry terms when asking about rates, and he was told multiple times that the person he was trying to meet was underage.

He was also charged in Hennepin County, but court records indicate the case was dismissed because the federal charge takes precedence.

Eichorn’s next appearance in federal court is scheduled for Wednesday morning. His attorney declined to comment at this time.

“The undercover technique, I would say, is the gold standard of investigative techniques,” said Jeff Van Nest, a retired special agent. “It really allows law enforcement to get in the mind of a potential perpetrator and have extended conversations over multiple days so there can be little doubt of what was going through the mind of an individual at the time a crime was committed. Many times it’s the best evidence that can be collected.”

The Hennepin County Attorney’s Office charged six other people as a result of the same operation. According to Van Nest, these investigations are very fluid to address the dynamic threat.

“It’s constantly changing and evolving and law enforcement has to stay one step ahead of it at all times,” he said. 

“The FBI could not do this alone and so many of these cases are shepherded, brought together and then the ultimate disposition is a call for the attorneys to make,” he said of the decision to prosecute the case in federal court.

Van Nest said these cases are a reminder to parents to remain vigilant about who children are speaking with online. He hopes these law enforcement operations serve as a deterrent. 

“Any potential perpetrator should always assume they are interacting with someone who is undercover,” said Van Nest.