South Dakotans for Better Marijuana Laws, the group behind Amendment A, the state’s voter-approved adult-use cannabis legalization measure, has filed a response to a lawsuit that challenges the constitutionality of the ballot initiative, according to the Rapid City Journal.

In a Dec. 7 court filing, the group argued that the case should be dismissed because voiding Amendment A would overturn the will of the people, the news outlet reported.

Last month, Pennington County Sheriff Kevin Thom and South Dakota Highway Patrol Col. Rick Miller filed a lawsuit to challenge the measure, arguing that it violates the state’s one-subject rule, as well as the amendments and revisions article of the South Dakota Constitution.

The plaintiffs are asking a judge to void Amendment A, and all parties have a Jan. 8 deadline to file and respond to motions, at which time a hearing will be held, according to the Rapid City Journal.