The Obama administration has yet to issue final rules implementing the law, but has said it would do so as part of its plan to reduce gun violence. Kennedy, noting his own struggle with addiction, said Obama should give an address to the nation when the final rules are issued.
"The denial of mental health treatment is a civil rights issue," Kennedy said.
The Center for American Progress organized Friday's event featuring Cooper, who has won accolades — and an Academy Award nomination — for his portrayal of a man suffering from bipolar disorder in the film "Silver Linings Playbook."
Cooper had screened the film the previous night at Walter Reed Medical Center. He and Kennedy said the screening turned into a discussion of mental health, particularly the trauma and post-traumatic stress disorder common among returning veterans.
Mental health is in the public spotlight following the Sandy Hook shooting, as part of a comprehensive plan to address violence. But most mentally ill people are nonviolent, and some policy experts fear that the association with a horrific school shooting will scare people away from getting the help they need.
The stigma associated with mental illness has to change in addition to federal policies, Cooper, Stabenow and Kennedy said, recounting their realizations that people close to them had dealt with bipolar disorder or other mental illnesses.