A Pennsylvania appeals court judge ruled that a lawsuit from a group of GOP lawmakers and candidates challenging the constitutionality of the state’s mail-in voting policy stands a good chance of succeeding.

Pennsylvania Commonwealth Judge Patricia McCullough wrote the opinion on Friday as a part of her assessment in calling for state officials to stop any additional steps toward certifying election results. The central legal argument for the lawsuit hinges on a law passed by the Republican-controlled legislature in 2019 called Act 77.