Sheriff's officials said that they arrested Marquise X. Montgomery, 22, in Elverta on Wednesday night, booking him into the Placer County Jail on suspicion of rape of a person unable to give consent.
Montgomery is suspected of sexually assaulting a woman in a Penryn care home where he was once employed. The 34-year-old woman was discovered a year ago to be about six months pregnant.
Police last year said she is mentally and physically disabled, legally blind and unable to feed or care for herself.
Sheriff's spokesman Lt. Mark Reed said investigators collected DNA samples from men the woman is believed to have had contact with in an effort to find a match with the baby's DNA.
However, Reed said they were unable to get Montgomery's DNA sample and he no longer worked at the care home. Once the baby was born, a DNA sample was collected from the child.
Eventually, investigators were able to collect DNA from a family member of Montgomery. They then compared the baby's DNA with the family member's DNA.
The result was a close enough match to obtain a warrant for Montgomery's arrest. Placer County detectives tracked him down to Elverta and he was arrested without incident.
The Bee is not identifying the care facility or the woman because of the sensitive nature of the case.
PHOTO CAPTION: Marquise X. Montgomery