A former Minnesota State Patrol trooper has admitted in court that he texted himself explicit images from the phone of a woman he had arrested last March.
Albert Kuehne, 37, detained the 25-year-old on suspicion of driving under the influence and took away her phone.
He then went through the phone without consent, sent himself three of her photos and then deleted the messages, investigators said.
The woman's boyfriend later found the outgoing texts on a linked device.
Mr Kuehne was placed on administrative leave in May 2020. He was arrested last June and charged with two felony counts of stalking with bias.
His admission of the crime on Tuesday was part of a plea deal that will see him instead convicted on one count of a gross misdemeanour for "non-consensual dissemination of private sexual images".
His lawyer did not immediately respond to a request for comment by the BBC.
A US Army reservist, Mr Kuehne is due to be sentenced later this month. He could face up to three years in prison.
The State Patrol fired him in October, and he has also since lost his law enforcement licence.
The 25 March incident in Minneapolis began when Mr Kuehne arrived at the scene of a single-car accident on the I-94 highway.
Suspecting the motorist - the 25-year-old woman who has not been named - was under the influence, he called paramedics to the scene and also took away her phone.
Video footage from inside Mr Kuehne's police cruiser shows him going through the phone as paramedics treat her.
Hours later, while using a laptop synched with the phone, the woman's boyfriend discovered that three explicit images had been shared with an unknown number, according to the criminal complaint.
He called the number and the person who answered identified himself as Mr Kuehne, the complaint states, prompting the lawsuit and subsequent investigation by the state Bureau of Criminal Apprehension.
When investigators seized Mr Kuehne's phone, they discovered three photos of the woman "either nude or partially nude", according to the complaint.
Mr Kuehne had initially denied the allegation.
Last June, when questioned about the incident by local outlet ABC 5 News, Mr Kuehne responded: "I really don't have anything to say about it."
On Tuesday, a state patrol spokesman called Mr Kuehne's actions "reprehensible and inconsistent with the core values of the Minnesota State Patrol".
In 2015, a California Highway Patrol officer was sentenced to three years of probation - but no jail time - after admitting he forwarded himself nude photos of two female DUI arrestees the previous year.
Forty-eight US states and the District of Columbia now have laws against capturing or distributing sexually explicit images, commonly known as "revenge porn".