Former substitute teacher in St. Paul charter school accused of sex with student

St. Paul City School is a public charter school that serves nearly 600 students in the heart of the capital city. But a former substitute teacher is accused of taking her relationship with a student too far.

A 17-year-old told investigators that 24-year-old Caitlin Thao had sex with him at the school in early February. He said it happened in an otherwise empty middle school classroom that Thao was substitute teaching in.

He also said Thao later invited him over to her place when her husband wasn't home, but he declined. When police received a report that a teacher was having a sexual relationship with a student, the school's executive director told them he was aware Thao had pulled the boy from class without reason or the authority to do so.

He said he was also getting complaints about Thao's inappropriate behavior with students.

But when Thao was asked to meet with one of the school principals, she immediately resigned, before school officials were made aware of the allegations by police.

Investigators say Thao told a social worker at Regions Hospital that she and the student had sex and that she had met him while teaching an English language learning class.

Police say Thao's husband found out about the sexual encounter and told the victim's mother in early March.

In a letter to parents, the interim executive director explained that the alleged incident occurred after school hours.

He also said the school followed all human resource processes when hiring Thao, including a criminal background check. 

Thao is charged with third-degree criminal sexual conduct for being in a prohibited occupational relationship.

If convicted, she could face a maximum penalty of 15 years in prison, a $30,000 fine, or both.