July 28, 2012— -- Colorado prosecutors are fighting shooting suspect James Holmes' attorneys over a package the alleged mass murderer sent to the school psychiatrist he was seeing.
Holmes' attorneys filed a motion Friday demanding that the court "immediately produce all discovery pertaining to the seizure of the package."
The filing revealed that Holmes was under the psychiatric care of Dr. Lynne Fenton, the University of Colorado's director of student mental health services, and it confirmed that he mailed a package to his doctors that authorities have since seized.
Holmes, 24, is accused of going on a shooting spree in an Aurora, Colo., movie theater during a midnight showing of "The Dark Knight Rises" on July 20. Twelve people were killed and 58 wounded.
ABC News went to Fenton's residence today, but no one answered the door.
Holmes' attorneys claim that seizing the package was a breach of confidentiality and they accuse the government of leaking the existence of the package to the media.
"The government's disclosure of this confidential and privileged information has placed Mr. Holmes' constitutional rights to due process and a fair trial by an impartial jury in serious jeopardy," his attorneys wrote.
Holmes' attorneys say the package is confidential communication between patient and doctor.
Fenton never received the package, but legal experts say that if Holmes ever made specific threats in their meetings, she had an obligation to report them.
"It's called duty to warn or duty to protect," threat assessment psychologist Marisa Randazzo said.
When investigators first found the package on Monday in the mailroom at the University of Colorado, where Holmes recently dropped out as a neuroscience student, they were so concerned that it -- like Holmes' apartment -- would be rigged with explosives, they sent in a robot to handle it.
Investigators are analyzing a notebook believed to be written by Holmes that could be a roadmap to a massacre.
Inside the notebook they reportedly found plans for a massacre, including drawings of a stick-figure gunman mowing down his victims.
The Arapahoe County District Attorney's office, representing the state, filed an objection to the motion and asked that it be denied. The DA said that the motion by Holmes's attorneys was "based on certain factual assumptions that are not established by evidence and that the People believe are of dubious validity, if not outright incorrect."
Holmes is expected to make his second court appearance on Monday where he will be formally charged for his alleged crimes.