A psychiatry professor joined MSNBC guest host Joy Reid on Saturday in taking issue with what Reid called an "artificial link" drawn by the National Rifle Association between mass shootings and the mentally ill.

"I think he was talking to a particular base," said Dr. Jonathan Metzl, who teaches at Vanderbilt University, about NRA CEO Wayne LaPierre's public statement on Friday. "His conference yesterday was actually full of a series of code words, historical code words, that were linked to mental illness and, to my mind, racial stigma. Some things about 'deranged killers,' 'hearing voices,' 'gangbangers on the loose,' all this kind of stuff, [which is] speaking to an anxiety about it, kind of 'Othering,' tied in to me to a mass paranoia: 'Here's why we need guns.' And there's a history to that kind of rhetoric in this country."

During his address -- the NRA'S first public comment on gun violence since the Dec. 14 attack on Sandy Hook Elementary -- LaPierre called for a national database for the mentally ill, even though, as he said, it "wouldn't even begin to address the much larger and more lethal criminal class: Killers, robbers, rapists and drug gang members who have spread like cancer in every community in this country."

The association LaPierre sought to make, Metzl said, is false, since people suffering from mental illness are more likely to be the victims of violence, rather than the ones committing it.

"What they're doing is, they're reinforcing a very problematic stereotype about the 'crazed, mentally ill lunatic' that really is not based in reality," he explained.

Watch Metzl discuss the dangers in the NRA's stigmatizing the mentally ill, aired on Saturday on MSNBC, below.

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