Idaho Code § 58-312

All persons using or occupying any state land without a lease from the state, and all persons who shall use or occupy state lands for more than thirty (30) days after the cancellation or expiration of a lease, shall be regarded as trespassers, and upon conviction shall be fined in a sum of not less than twenty-five dollars ($25.00) nor more than $500, or shall be punished by imprisonment in the county jail for a term of not to exceed six (6) months, or by both such fine and imprisonment. Any criminal suit under this section may be instituted by any person against any trespasser, and regardless of the fact whether or not the said land is under lease to any person other than the trespasser, and in case of a lessee, the sureties of his bond shall be liable to a civil suit for all damages sustained by the state by reason of the trespass. Any suit for civil damages against a trespasser, may be instituted by the attorney general in the name of the state, or in the event the land trespassed upon is leased, such suit for civil damages may be brought by the lessee in his own name: provided further, it shall be the duty of the prosecuting attorney to commence and prosecute all criminal actions under this section, arising in his county.