A libertarian law firm has filed a lawsuit in Indianapolis against President Biden’s student debt cancellation plan.

The Pacific Legal Foundation filed their challenge Tuesday, the Associated Press reports. The California-based firm said Biden’s plan is illegal, and will only make taxes worse in some cases.

The main argument against the plan is that certain states will tax the amount of debt that is forgiven, meaning many Americans will still have to pay for a program meant to benefit them financially. The states that are currently planning to implement these taxes are Indiana, Arkansas, California, Minnesota, Mississippi, North Carolina and Wisconsin.

Indiana resident and attorney Frank Garrison works for the Pacific Legal Foundation, and is the plaintiff in this case. Garrison is already part of a program that would allow his loans to be forgiven without taxation. So, Biden’s plan could hinder him financially.

Other conservative groups have been opposed to the idea of debt forgiveness since the plan was announced. They argued that the plan would force all Americans to pay for loans, even if they did not go to college or personally take out loans.

This lawsuit is trying to put a stop to the plan, at least until its legality is determined. It says the plan will be a “profound and transformational policy that will have untold economic impacts.”