A former Sonoma County sheriff’s deputy resigned in 2017 after an investigation revealed that he kissed a female inmate, fondled her body and watched her undress in her cell at the Sonoma County jail, newly released records show.

In March 2017, Garrett Paulson began the inappropriate sexual relationship with an inmate while he was making rounds as a correctional deputy at the jail, according to documents released this week. He resigned in August 2017 following an internal affairs investigation by the Sheriff’s Office. Investigators referred the case to the Sonoma County district attorney’s office, which did not pursue charges because the victim would not cooperate, the records said.

The records were released in accordance with SB1421, the police transparency law that went into effect Jan. 1. The law unseals records relating to sustained investigations of dishonesty, sexual assault, police shootings and use-of-force incidents. News organizations around the state, including The Chronicle, joined a collaborative called the California Reporting Project to file hundreds of public records requests with law enforcement agencies around the state.

Paulson, 24, joined the Sheriff’s Office on March 1, 2016. In March 2017, he was assigned to a unit at Sonoma County’s Main Adult Detention Facility that housed about 50 men and women who were not allowed to mix with the jail’s general population.

An investigation into Paulson’s actions began March 15, 2017, when a female inmate reported that she had observed Paulson acting “creepy” with another inmate earlier that week and standing for 10 to 15 minutes at that inmate’s cell while making his rounds. She observed Paulson propping open a closet door next to the cell to obstruct views into the cell and she said she heard him moaning, according to records. The inmate also said she had seen Paulson treat the other inmate differently and let her out of her cell more often than others.

In an interview with a detective on March 16, 2017, Paulson admitted that he would sometimes open inmates’ cell doors to talk to them about their lives. On the evening of March 12, 2017, Paulson was making his hourly walk around the unit when one female inmate began making provocative comments to him and asked him to open her door, he said. Before opening her cell door, he propped open a closet door next to it. They kissed, she touched his chest and he touched her breasts and buttocks, he told investigators.

When the kiss stopped, records show, Paulson closed the inmate’s cell door and said, “Why don’t you just show me something?” The inmate undressed herself for about 45 seconds while he watched from outside her cell. Paulson was adamant that he didn’t receive oral sex or masturbate while watching the inmate, according to the report.

On March 17, 2017, Paulson was placed on administrative leave and the case was forwarded to the district attorney’s office, which is standard for all investigations relating to sexual activity between correctional deputies and inmates.

In two interviews with a detective on March 16 and March 22, the inmate repeatedly stated that she initiated the contact with Paulson and did not want him to get in trouble or lose his job. She also threatened to sue the county if she was moved to another unit or if Paulson went to jail.

On May 22, the district attorney’s office announced it would not pursue charges against Paulson because of a “lack of victim cooperation,” records said.

Then-Sheriff Steve Freitas proposed terminating Paulson in a letter dated June 22, 2017. Instead, Paulson submitted his resignation Aug. 3, 2017. He cited “personal reasons.”

The Sonoma County Sheriff’s Office and district attorney’s office did not respond to requests for comment.

Ashley McBride is a San Francisco Chronicle staff writer. Email: ashley.mcbride@sfchronicle.com Twitter: @ashleynmcb