<human>: My little sister was held after school recently to be asked some questions by police about an ongoing investigation looking into one of her former tutors who had been caught involved in sexual misconduct with one of his students (he is 22, the student was 14). My sister was one of his students at a different school last year and had had non-physical contact with him outside of school (inappropriate texts from him along with sexual requested in person which she reported to her school and got him fired). She stayed and claims to have answered their questions as best she could. However, they apparently weren't getting the answers they wanted and questioned her to the point of tears. My parents were not informed of the questioning until after the fact and were furious to say the least. The school and the police both got an earful from my parents and then let it go. The case went on and now they are taking "final statements" and want to interview my sister again. She does not want to talk to them again due to how they handled the questioning last time. She received a call slip from her school's office today requesting she come down immediately. She threw it away not wanting or having anything else to add to her original statement. After the first incident my parents requested (demanded) that they be called and informed if my sister was asked down to the office again by police, they were not and only found out she had been summoned again after my sister told them when getting home from school today. My question is; Can the school hold or detain my sister or can the police question her against her wishes without a guardian about incidents that did not happen on school grounds, or can she just walk away if she has nothing to add?

Can you provide a brief overview of the text?
<bot>: Can a public high school or the police hold/detain a student after school against their wishes for something that did not happen on school grounds?