A man whose father founded Gloriavale says there's no easy route out of the commune for those wishing to escape.

The religious cult has hit the headlines after a string of ex-members spoke out about their experiences, with claims of brainwashing and sexual abuse.

Phil Cooper says he can recall his own plight around 30 years ago, when he escaped with his young family.

"I had six young children, single dad trying to survive, I also went through those same questions of 'is it worth it, is it easier' and I can tell you it would have been many times easier to go back."

Cooper says the door may be open to members who want to leave - but leaving without support is near-impossible.

"Families are cut off from each other, husbands are cut off from their wives, children are cut off from their parents.

"What we want is for an openness that families can come and go as they please."

Police yesterday sent out a formal request for ex-members to come forward with information on their experiences.