The leader for Iowa Senate Democrats is punishing Sen. Nate Boulton by denying him any committee assignments as he faces an ethics investigation into allegations of sexual misconduct.

Senate Minority Leader Janet Petersen on Friday kept Boulton, a Des Moines Democrat, off her list of committee appointments for the legislative session that begins next month.

“I will defer making any committee assignments for Senator Boulton until the Senate Ethics Committee completes its ongoing investigation into the complaint filed against him," Petersen, also a Des Moines Democrat, said in a statement.

The move is mostly symbolic since Democrats continue to be in the minority at the state Capitol and don't have definitive power on what legislation reaches Republican Gov. Kim Reynolds' desk.

Still, Boulton will have even less say in what proposed bills move through the GOP-controlled Legislature. It is unclear if Boulton could be appointed to committees if an investigation clears him.

Boulton on Friday did not immediately return calls seeking comment.

Boulton, an attorney who was once a rising star in his party, was accused earlier this year by three women of inappropriate sexual contact in social settings that predated his 2016 election as a state lawmaker.

Boulton, who had been in a crowded field of Democratic nominees for governor at the time, dropped out of the race one day after the Des Moines Register reported on the allegations.

Boulton did not deny the allegations at the time but he said he did not "have the same recollection." Petersen and other Democrats called on him to resign.

Months later, Boulton claimed he had made progress with an alcohol addiction and planned to return to the Capitol as a senator in 2019.

Boulton had a prominent role

For the first half of his four-year term, Boulton served as a ranking member on the Senate Labor and Business Relations Committee.

The position allowed him to speak up against a Republican-led effort to remove most collective bargaining rights for public workers. His prominent role in the contentious debate garnered attention and support from union groups that later supported his candidacy for governor.

Boulton also served on legislative committees for appropriations, commerce and judiciary.

Next year, he will have none of those spots. Democrats would not say whether additional action will be taken against Boulton, like denying him legislative staff.

Ethics complaint filed against him

Last month, one of the women who accused Boulton of misconduct filed an ethics complaint against him.

MORE:Capitol harassment: Nate Boulton's case will test Senate's new ethics rules

Sharon Wegner, a Des Moines attorney, filed a complaint that accused Boulton of pursuing her at a bar in November 2015 and repeatedly grabbing her buttocks without her consent. At the time, Boulton was running for his Senate seat.

The Senate Ethics Committee that's expected to investigate the complaint against Boulton faces potential hurdles. Chamber rules don’t specify whether the committee — a bipartisan group of three Republicans and three Democrats — has jurisdiction in situations that allegedly occurred before a lawmaker’s election.

The top two Republican senators who currently oversee the committee did not immediately return messages Friday.

Follow the Register on Facebook and Twitter for more news. Barbara Rodriguez can be contacted at bcrodriguez@registermedia.com or on Twitter @bcrodriguez.

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