HACKENSACK, N.J. – A former New Jersey sex education instructor lost his teaching license last month – a year after he was sentenced to prison for taking a hands-on approach with a 16-year-old female student.

Donald DeWitt, 66, taught biology and human sexuality at Bergen County Academies until he was arrested in April 2015, shortly after the sister of one of his students raised the alarm about the teacher’s sexually charged messages to her sibling, NJ.com reports.

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“The victim’s sister discovered sexually explicit email correspondence between the victim and (DeWitt) and advised their mother of her findings,” former Bergen County Prosecutor John Molinelli told the Hackensack Daily Voice.

“The victim’s mother then contacted her local police department, who notified the Bergen County Prosecutor’s Office Computer Crimes Unit,” he said. “The victim’s mother and sister advised her that she needed to speak to law enforcement authorities about this information.”

New Jersey issued DeWitt a teaching certificate for biological science in 1993, and state officials formally revoked the privilege on July 27.

“The Board sent DeWitt the Order to Show Cause by regular and certified mail on December 20, 2017. The Order provided that DeWitt must file an Answer within 30 days. DeWitt filed an Answer on February 6, 2017. In that Answer, DeWitt admitted to all of the allegations in the Order to Show Cause,” according to the State Board of Examiners’ Order of Revocation. “He also apologized for the ‘embarrassment and dismay I have caused.’”

“In this case, DeWitt has been convicted of an offense involving sexual conduct with a minor,” the order read. “The Board therefore finds that the only appropriate response to DeWitt’s conduct is the revocation of his certificate.”

The Wyckoff Patch reports DeWitt was one of the first teachers hired by Bergen County Academies in 1992, and he holds a doctorate in cardiovascular physiology.

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The disturbing case is one of the latest in an epidemic of educators sexually abusing students in schools across the United States.

After years of ignoring the problem, lawmakers in several states are working on legislation to address loopholes in mandatory reporter laws and failures in the hiring process that have helped perpetuate the abuse.

Lawmakers in Texas and Nevada approved legislation this year to crack down on educator sexual misconduct, while legislators in New Jersey, Massachusetts, and other states are currently reviewing similar bills.

In total, only seven states have enacted laws to specifically address educator sexual misconduct and abuse of students: Washington, Oregon, Missouri, Pennsylvania, Connecticut, Nevada, and Texas.

The nonprofit Stop Educator Sexual Abuse Misconduct and Exploitation (S.E.S.A.M.E.) is currently pressuring lawmakers in other states to comply with federal laws that mandate states adopt policies to stop educators from sexually abusing students.