The Madison West High School student accused of raping a fellow classmate in a secluded stairwell at the school last month was officially charged Thursday with second-degree sexual assault.

It remains unclear whether the student will be charged as an adult.

The 16-year-old suspect, arrested only a few hours after the assault occurred, had previously served time in a juvenile facility after being convicted of stealing a car and damaging property.

The sexual assault at West High sparked questions of student safety, leading to a district-wide investigation into the criminal records of students, which revealed one out of 100 students in the district had been convicted of a crime in their lifetimes.

District officials did not specify the degree of severity of the convictions, which range from shoplifting and fighting to felonies.

East High School has the highest number of convicted students with 88.

Schools whose students were figured into the findings include high schools La Follette, with 45, Memorial, with 34, West, with 31, and Shabazz, with five, a number of middle schools, and Sandburg Elementary School, with one.

State law requires districts to educate children with criminal records unless the students have been expelled for an incident taking place on school grounds or at a school-sponsored event.

Since his arrest, the suspect had been incarcerated at Ethan Allen, a state corrections school in Wales, Wis.

Upon returning to school several days after the mid-September attack, the victim, also 16 years old, was beaten in a hallway of the high school.

The suspect’s sister, also a student at West, was arrested in connection with the victim’s beating and later released on bail.