A Richardson teacher has been arrested with having an improper relationship with a student.

Officers told NBC 5 the girl's parent contacted them on Nov. 20 after the 16-year-old received unwanted texts and emails from Richardson High School English teacher James Quigley.

Once police interviewed the girl, they discovered the teenager and Quigley, 34, engaged in sexual contact between May 1, 2014 and June 30, 2014.

The girl told officers Quigley approached her with a "written contract" and said if she signed it, he would give her a better grade in his class.

The contract prohibited the girl from tell anyone what was going on and from going near Quigley's wife, who is also a teacher at Richardson High School.

The girl also told police that on another occasion, Quigley told her they could go out to movies together and be "friends with benefits."

Quigley has been charged with having an improper relationship between an educator and a student, as well as sexual assault.

Richardson police are asking that any additional witnesses come forward and call them at 972-744-4800.

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