A former Westminster police officer has pleaded guilty in federal court to violating the civil rights of a woman he sexually assaulted in 2017 while he was on duty.

Curtis Arganbright, 42, faces up to 10 years in federal prison when he is sentenced in March, federal prosecutors say.

Arganbright’s case drew outrage after he was sentenced to just 90 days in jail after originally being prosecuted in Adams County court for the assault.

In that state case, he pleaded guilty in November 2018 to unlawful sexual contact and official misconduct related to his crimes against the woman.

Federal authorities then stepped in to re-investigate and prosecute the case over the summer and he was charged in the case in federal court last month.

“As federal prosecutors, our job is to ensure that justice is always served,” Colorado’s U.S. attorney, Jason Dunn, said in a written statement Monday. “When we see an injustice, we will not hesitate to step in, particularly when it involves vulnerable people or those in positions of power.”

Arganbright was giving his victim, a 36-year-old woman, a ride in his police vehicle to her home from St. Anthony Hospital North in Westminster early in the morning of Aug. 24, 2017, when he pulled off the road, handcuffed her and sexually assaulted her, prosecutors and court records say.

Former Westminster police Officer Curtis Arganbright. (Provided by CBS4)

As part of his plea agreement with federal prosecutors, Arganbright has agreed to never again seek employment as a police officer. He also must register as a sex offender.

The federal charges against Arganbright represent a rare intervention in a state case by federal prosecutors, especially one involving a police officer.

Arganbright is free on bond pending sentencing.

Our articles are free to read, but not free to report Support local journalism around the state.

Become a member of The Colorado Sun today! $5/month $20/month $100/month One-time Contribution

The latest from The Sun