— A former middle school teacher who had illegal sexual contact with a student was allowed to resign in 2014 from the Hollis school district with the understanding she could keep her teaching credentials, the student’s father alleges in court filings.

The teacher, Jennifer Caswell, is awaiting sentencing on sexual assault charges involving the boy, who was 15 at the time.

A year and a half ago, Caswell was embarking on a career as a middle school English teacher under her married name, Jennifer Sexton. She has since lost her job and state teaching credentials, gotten divorced, appeared on national TV and become a convicted sex offender.

In a federal lawsuit filed April 1, the student’s father accuses the school district of attempting a cover-up after at least two people witnessed Caswell engaged in sexual acts with the boy in her classroom. At the time, the incident was reported to an administrator but not to the father, police or the Department of Human Services, according to the lawsuit, which also names the Hollis Independent School District, Hollis Public School Board and the superintendent.