MILLBRAE (CBS SF) – A former middle school teacher who pleaded no contest to felony lewd acts with a minor was sentenced Tuesday to 120 days in jail and three years’ probation, according to the San Mateo County District Attorney’s Office.

Heather Amanda Butts, 42, was arrested in August 2016 on suspicion of having an inappropriate relationship with a 15-year-old high school student. The girl was 13 when the relationship began, prosecutors said.

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Police responded to an anonymous report of a white van parked in front of Lomita Park Elementary School in Millbrae with Butts and the victim kissing inside. Officers found her alone in the vehicle, but the victim was found nearby.

The victim initially told investigators that nothing inappropriate had happened, but later admitted that she had been kissing Butts and said the two were in love. Further investigation found explicit text messages and evidence of sexual conduct going back to October 2015.

Heather Amanda Butts (San Mateo County Sheriff’s Office)

At the sentencing hearing Tuesday, Butts allegedly referred to the victim as a “sexually sophisticated partner,” and said that she had saved the victim’s life by keeping her from suicide at a time when she’d been distraught, prosecutors said.

“We occasionally hear that from defense attorneys trying to put on the best face for their client, but judges almost always reject that,” District Attorney Steve Wagstaffe said.

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“At 13, dealing with an adult, you can in no way attribute anything to the sexual sophistication of the victim,” Wagstaffe said. “It’s a non-factor, irrelevant in our minds.”

He did note that the victim had told investigators that she did not want Butts prosecuted or convicted.

“She wanted nothing to do with it,” Wagstaffe said.

Butts will be required to register as a sex offender, despite a motion from her attorney, and will be prohibited from associating with minors or frequenting places where children congregate like parks, schools and pizza parlors, Wagstaffe said.

Defense attorney Paula Canny did not respond to a request for comment on her client’s behalf.

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