A former girlfriend of Sean Combs who was once part of the government’s sex-trafficking case against him wrote a letter in support of the music mogul’s release from jail ahead of his sentencing for prostitution-related offenses.

The woman, Virginia Huynh, was included in the indictment as one of the women Mr. Combs was accused of coercing into sex. Often referenced in court proceedings as “Victim-3,” Ms. Huynh did not ultimately testify at the trial, and her departure from the case was not publicly explained.

Ms. Huynh’s letter was filed in court by Mr. Combs’s lawyers on Sunday to bolster their argument that their client should be granted bail. Addressing Arun Subramanian, the judge overseeing the case, Ms. Huynh spoke highly of Mr. Combs, describing him as a “family man” who, she believed, would adhere to bail conditions.

“Our relationship, like many, was not always perfect, we experienced ups and downs, and mistakes were made, but he was willing to acknowledge his mistakes and make better decisions in the future,” the letter said. “Over the years that followed he made visible efforts to become a better person and to address the harm he had caused.”

Mr. Combs, known as Diddy and Puff Daddy, has vehemently denied sex trafficking anyone since the start of the case and has maintained that his sexual relationships with the women were fully consensual.

A jury acquitted Mr. Combs last month of sex trafficking and racketeering conspiracy, the most serious charges against him, at the conclusion of an eight-week trial at Federal District Court in Lower Manhattan. He was convicted on two lesser counts of transportation to engage in prostitution, violations related to voyeuristic sex marathons known as “freak-offs” and “hotel nights” that involved Mr. Combs, his girlfriends and hired male escorts. Each carries a maximum sentence of 10 years.