A Yellowstone County prosecutor says he believes a state judge erred in giving a 30-day prison sentence to a former teacher convicted of raping a 14-year-old girl who later committed suicide.

County Attorney Scott Twito said Thursday that a legal review of the case suggests former teacher Stacey Rambold should have received at least two years in prison.

District Judge G. Todd Baugh has been sharply criticized over Monday's sentencing, in which he said the victim was "older than her chronological age" and had some control over her relationship with Rambold.

Twito said he's working with the appellate division of the state Attorney General's Office on whether to appeal. A final decision has not been made.

Prosecutors originally sought a 20-year sentence with 10 years suspended.