Gov. Sam Brownback has signed a proclamation calling the Kansas Legislature into special session Sept. 3. Legislators will rewrite a state law allowing judges to sentence convicted murderers to serve at least 50 years in prison.

Brownback had a Tuesday afternoon signing ceremony in the Statehouse rotunda. He had already announced the special session, but a proclamation is required to convene it.

The governor was responding to a recent U.S. Supreme Court decision raising questions about the constitutionality of the state’s “Hard 50” law.

Legislators and prosecutors said a special session is necessary to rewrite the law and protect public safety.

Brownback and top legislators expect the session to last no more than three days.