This week AC360° presents a three-part series investigating allegations of abuse at the Pinehaven Christian Children’s Ranch. The founder, Preacher Bob Larsson, asks new students to sign a document stating they understand the religious nature of the school and believe the bible to be the word of God. Because the Montana boarding school is a faith-based institution, the state has no authority to oversee or regulate it.

Pinehaven Christian Children’s Ranch in western Montana doesn’t deny their use of “tough love” techniques on students. In the past, one house parent would apply pressure to the children’s necks to control their behavior, a practice Pinehaven says is no longer permitted. Several former students and employees say they experienced or witnessed physical and emotional abuse. Preacher Bob Larsson, who’s been the school’s owner for almost 40 years, denies the allegations and tells CNN’s Gary Tuchman that their methods of discipline are not abusive.