An Oklahoma judge ruled the state’s execution law unconstitutional Wednesday because its privacy provision is so strict that it that prevents inmates from finding out the source of drugs used in executions, even through the courts.

After condemned inmates gasped or complained they were “burning” during executions in January, inmates Clayton Lockett and Charles Warner asked Oklahoma prison officials who was making the drugs that would kill them and whether the material was pure.

However, under state law, no one is allowed to disclose the source of drugs used in a lethal injection — even if an inmate sues and seeks the information as part of the discovery process. Oklahoma County District Judge Patricia Parrish said that prevents the inmates from exercising rights under the Constitution.

“I think that the secrecy statute is a violation of due process because access to the courts has been denied,” Parrish ruled.