Special Education Teaching Assistant Arrested on Child Abuse Charges

In April 2023, the Washington County Sheriff’s Office opened an investigation after learning a special education teaching assistant in the Hillsboro School District may have sexually assaulted a student away from school property.

Detectives with the Violent Crimes Unit were assigned and learned 22-year-old Yessenia Manriquez Casillas, who lives in Beaverton, was an employee of the Hillsboro School District and worked at Century High School.

Manriquez Casillas picked up the student at a celebration and then sexually abused the person. In June, a Washington County grand jury heard evidence on the case and issued an indictment for Manriquez Casillas’ arrest.

On June 14, 2023, deputies with the Sheriff’s Office Criminal Apprehension Team arrested Manriquez Casillas at her home and booked her into jail on four counts of sexual abuse in the second degree.

During the investigation, detectives were told there may be additional victims and are asking anyone with information to call the Sheriff’s Office at 503-846-2700.