Republicans in the Montana Legislature passed several new laws this session they say will protect election integrity.

The Montana Public Interest Research Group (MontPIRG) filed suit in Missoula over a law that says people who move to Montana temporarily are not eligible to vote. The law requires prospective voters to self report whether they’re a temporary resident for work or an educational program.

State law says people are otherwise considered residents if they live in a Montana county for more than 30 days.

MontPIRG argues the law unconstitutionally discriminates against students.