MODESTO — A former Stanislaus County sheriff’s deputy has been sentenced to nine years in state prison after being convicted of sexually abusing his daughter over an eight-year period, prosecutors said.

Matthew Dessert, 42, was found guilty by a jury of multiple felony charges, including continual sexual abuse of a child, lewd acts with a minor, and sexual battery, District Attorney Jeff Laugero announced Tuesday. The Honorable Judge Mangar imposed the sentence, which also includes a 10-year parole term and lifetime sex offender registration.

Dessert was arrested in September 2023 after a school counselor contacted the sheriff’s department regarding a student who disclosed being a victim of long-term sexual abuse. The teenager told detectives the abuse began when she was nine years old.

At the time of his arrest, Dessert was employed as a patrol deputy with the Stanislaus County Sheriff’s Office, where he had served since 2014. Authorities said he voluntarily came in for questioning and was subsequently taken into custody.

Charges filed against Dessert included continual sexual abuse of a child, penetration with a foreign object of a minor under 18, and physical abuse. Prosecutors said the case was built on the victim’s detailed account, corroborated by investigative findings.

Dessert will serve his sentence in state prison and is barred from future law enforcement employment.