Young offenders in Jersey should not serve their sentences in an adult prison, a Council of Europe group says.
A committee from European Committee for the Prevention of Torture said courts should send youngsters to the island's Greenfields secure centre.
Jersey's prison service said it backed the report but it did not have enough facilities for young people outside of La Moye prison.
Inspectors can visit detention centres at short notice.
They visited Jersey's police station, prison, the secure home for young people at Greenfields and the psychiatric unit at St Saviour's Hospital.