EVERETT — A Marysville man is being prosecuted for child molestation after he reportedly offered a surprise confession about repeatedly assaulting a girl 15 years ago.

Prosecutors say Christian Flores, 37, was in jail on an unrelated warrant last month when he asked to speak with a detective. He reportedly told a Lynnwood police detective that he had been struggling with his guilt, and he wanted to provide justice for the victim, Snohomish County deputy prosecutor Jarett Goodkin wrote in court papers.

Flores allegedly detailed numerous occasions when he assaulted his former girlfriend’s 2-year-old daughter. He reported incidents of sexually abusing the girl. He also reportedly told detectives that he severely injured the child, including twisting her arm until her collarbone broke, court papers said.

Flores told detectives that the last time he assaulted the girl was in 1997. He said he was so frightened by what he’d done that he moved out a few days later. He said during that incident he picked the toddler up by her feet and threw her down on a futon. He said she struck her head and lost consciousness. Flores said he had to resuscitate the girl. He said at the time he thought he may have killed her.

The detective asked Flores why he was confessing to these crimes. His response reportedly made little sense.

“I think that I’m such a (expletive) piece of (expletive) that no matter how much evidence they gather I can probably get off on that crime,” Flores reportedly said. “So, I want to make sure (the victim) gets justice.”

Flores made a brief appearance Monday in Snohomish County Superior Court. He pleaded not guilty to the charge. He was being held on $200,000 bail.

After speaking with Flores last month, detectives contacted the girl’s mother. She told police that Flores, who was her live-in boyfriend, baby-sat her daughter while she was attending college in the late 1990s. She remembered her daughter being hospitalized for a broken collar bone and pneumonia. She said Flores was caring for the girl when she was injured. He never explained the broken bone, and she was too afraid to ask. The woman told investigators that she had been repeatedly beaten by Flores. She said she believed that she was the only person he was abusing. She described him as extremely violent and told detectives that during one “bender,” Flores killed the couple’s pets, including a lizard, kittens and a rabbit.

Detectives later interviewed the woman’s daughter, now 18. She characterized Flores as a violent man and said she witnessed him beat her mother.

She also remembered him hurting her. The woman said she recalled Flores throwing her against a wall. She believed he broke her collarbone. The woman also told investigators that she had memories of Flores inappropriately touching her when she was a child between the ages of two and three. She remembered feeling uncomfortable and fearful. She also recalled being in pain.

Detectives reviewed medical records for the girl from 1996 and 1997. The records indicate that concerns were raised about child abuse because of injuries to the girl, including a broken clavicle and a facial bruise.

The court papers don’t say whether the allegations were investigated back then.

Diana Hefley: 425-339-3463; hefley@heraldnet.com.