Some Iowa teachers convicted of sexually abusing students have been placed on probation rather than sentenced to prison, despite a state law requiring they spend time behind bars, a Des Moines Register investigation has found.

The law, passed in 1997, specifically prohibits anyone who is a “mandatory reporter” of child abuse — such as a teacher, social worker or psychologist — from eligibility for probation. It was passed to hold educators and others in positions of power and influence over children to higher standards of accountability.