Anchored by Jake Tapper, The Lead airs at 4 p.m. ET on CNN.
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(CNN) – Fort Hood shooter Spc. Ivan Lopez, an Iraq war veteran, was being evaluated for post-traumatic stress disorder before he opened fire at the Fort Hood Army post in Texas on Wednesday, killing three and wounding 16 before taking his own life. He had a history of depression, anxiety and other psychiatric disorders.
Finding out why Lopez went on a shooting rampage is going to be complex, there will not be a simple precipitating factor, says Rep. Tim Murphy, R-Pennsylvania, a clinical psychologist.
"I'm not here to diagnose him but when they talk about medications, it's very important to understand that when a person is on medications, when they're starting a medication, adjusting the medication, adjusting the dose, there can be a number of side effects, which, for example, there can be an increase in suicide, there can be an increase in hostility, anxiety, worry," Murphy said in an interview with CNN's "The Lead with Jake Tapper."
The congressman, who has pushed legislation to address mental health problems, stressed that Lopez' actions are atypical of people who suffer from mental health problems. Most people with anxiety, depression, sleeplessness, traumatic brain injury and posttraumatic stress do not have any propensity to violence.
"What we don't want to have is a situation where other soldiers are now afraid to go and get help because they think they are going to be branded as a killer, there will be a stand-down, they'll be taken away from their responsibility. They won't get promoted," said Murphy.
"That's the stigma the military has, to its credit, fought so hard for the last two years," said the congressman.
For more of our interview with Rep. Tim Murphy, check out the video above.