Hector Paez, 31, had been on paid leave for five months, but when he was arrested on Monday, he was placed on unpaid leave.
Denver District Attorney Mitch Morrissey's office and police say Paez has been formally charged with second-degree kidnapping, sexual assault and attempt to influence a public servant. Paez will appear in court again Friday morning.
"These are very serious charges," Denver DA spokesperson Lynn Kimbrough said.
The 36-year-old woman told investigators that on May 16, Paez pull over in his squad car next to the woman, who was walking. He began questioning her and found out she had an active warrant out of Jefferson County.
"The allegation is that using that information, he coerced her to perform a sexual act to avoid taking her to jail," Kimbrough said.
Paez, who appeared in court Tuesday, is being held at the Douglas County Jail on $100,000 bail.
"If convicted on a sexual assault count and convicted on the kidnapping, there would be a lengthy prison term that would be set as the minimal number of years, but potentially it could be a life sentence," Kimbrough explained.
The charges follow an internal affairs investigation prompted by a call by the victim. Kimbrough credits the victim with pushing this case forward.
"Were it not for her coming forward to share her complaint, the internal affairs bureau would have had no way of knowing and would not have been able to start an investigation," Kimbrough said. "Certainly the credit goes to our victim who came forward and the result will be criminal charges that will be filed tomorrow."
Paez has been with the force since 2006, and worked out of the District 4 substation. He declined an interview request made through jail administrators.
Neighbors say he kept to himself.
Many of them were wondering why Paez hadn't been driving his squad car home since mid-May.
"I think you have to say it's a sad day, it's a sad day, but we have a victim that we are going to advocate for, the charges are going to be formally filed tomorrow, and we'll go forward," Kimbrough said.
(KUSA-TV © 2010 Multimedia Holdings Corporation with The Associated Press)