A Palo Alto man accused of molesting his two stepdaughters was sentenced to 20 years in state prison in San Mateo County Superior Court Wednesday, Dec. 5, Assistant District Attorney Karen Guidotti said.

Robert Sparhawk, 48, had already pleaded no contest on the morning of his jury trial Oct. 1 to three felonies: felony continuous sexual molestation and two counts of child molestation. He was originally charged with six counts for molesting the girls from 2003 to 2007 and faced life in prison, Guidotti said.

Sparhawk, who was a technology analyst for a Mountain View company, was tried in San Mateo County because the crimes occurred when the family lived in San Mateo. But they eventually moved to Palo Alto, according to the district attorney's office. The abuse started when the girls were 11 and 12 years old.

The victims did not tell their mother because she seemed very happy in the marriage and they did not want to hurt her happiness because she had a dismal marriage to her first husband, the district attorney's office said.

In 2011, one of the victims mentioned the molestation to a friend, who told authorities. Both girls initially denied the crimes to Palo Alto police, but their mother persisted in getting them to talk to investigators. The girls disclosed years of abuse, the district attorney said.

Sparhawk made numerous admissions during an arranged phone conversation. He was arrested after attempting suicide, according to the district attorney.

Guidotti said Sparhawk must serve at least 85 percent of the 20 years under state law. He received 469 days of credit for time already served. He must register as a sex offender when he is released from prison, and he must make restitution to his victims.

Guidotti said prosecutors are satisfied with the sentence.

"Oftentimes, when we reach a large, agreed-upon term it's so the children don't have to testify," she said.

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