This was an accident and a panic and she is so, so sorry," Tichelman's public defender Jerry Christensen told the court

Credit: Dan Coyro/Santa Cruz Sentinel/AP

Alix Tichelman, the California call girl accused of injecting Google executive Forrest Timothy Hayes with a lethal dose of heroin, pleaded guilty to involuntary manslaughter and other charges on Tuesday.

She was sentenced to six years behind bars, though she’s only expected to serve three of those years, the Santa Cruz Sentinel reports.

“This was an accident and a panic and she is so, so sorry,” Tichelman’s public defender Jerry Christensen told the court.

Hayes was found dead onboard his yacht in November 2013. Camera footage from the boat showed Tichelman injecting Hayes with the drug, then abandoning him to die, finishing a glass of wine before leaving the yacht.

Tichelman was arrested last July after she was lured back to Santa Cruz, where the crime took place, in a prostitution sting. Authorities told PEOPLE that Tichelman was found with heroin on her at the time of her arrest.

Santa Cruz Deputy Police Chief Steve Clark described Tichelman’s behavior in the video as cold, adding that she later did Google searches of herself “looking for information on and looking for ways to get herself out of it.”

Hayes was not the first person involved with Tichelman to die in this manner. Her former boyfriend, Dean Riopelle, was hospitalized in Milton, Georgia, for a heroin overdose in September 2013 and died a week later.

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