In February 2017, President Donald Trump repealed a regulation from former President Barack Obama that made it more difficult for those with mental illness to have a gun.

In wake of the shooting at Marjory Stoneman Douglas High School in Parkland, Florida, Trump has attacked the mentally ill, implying they are the vast majority of those responsible for mass shootings.

"So many signs that the Florida shooter was mentally disturbed," Trump tweeted one day after the Parkland massacre. "Even expelled from school for bad and erratic behavior. Neighbors and classmates knew he was a big problem. Must always report such instances to authorities, again and again!"

It's similar to the claims Trump has made in the past.

“Mental health is your problem here," Trump said in wake of an October in wake of a shooting at a First Baptist Church in Texas. "This was a very … deranged individual." He went on to say shooter Devin Patrick Kelley, had “a lot of problems over a long period of time. But this isn’t a guns situation.”

The "mental health problem" has become a talking point for pro-gun activists. Yet, when given the opportunity to do something about it, Trump went the opposite direction.

The decision from Trump made good on his Jan. 2016 campaign promise to stop Obama's gun regulations.

"There's an assault on the Second Amendment," Trump said to a crowd in Biloxi, Mississippi. "You know Obama's going to do an executive order and really knock the hell out of it. You know, the system's supposed to be you get the Democrats, you get the Republicans, and you make deals. He can't do that. He can't do that. So he's going to sign another executive order having to do with the Second Amendment, having to do with guns. I will veto. I will unsign that so fast."

Obama's rule would have given the National Instant Criminal Background Check System, the system used for gun sales, access to Social Security Administration date, including names of those earning mental health benefits. It was his intent to strengthen the federal background check system after the shooting at Sandy Hook Elementary in Newtown, Connecticut in 2012.

After Obama signed the order, the Republican-led Congress stepped in and used the Congressional Review Act to rescind the order. The rarely-used procedure allows all regulations passed by the White House to be stopped if they're done in the final 60 days of a new administration. The White House recieved the repeal on February 15, 2017 and Trump signed it Feb. 28.

Many have argued the order was an invasion of privacy and the order was opposed by the American Civil Liberties Union. Yet, when given the opportunity to take action against those Trump and gun-activists blames for mass shootings, the president went another direction.

The order would have prevented approximately 75,000 people with mental disorders from having access to weapons, Snopes said.

Psychologists have also opposed the Obama order, saying that it stigmatizes those with mental illness. According to mental health experts, those with mental illness are more likely to harm themselves than others.

“The concept that mental illness is a precursor to violent behavior is nonsense,” Dr. Louis Kraus of Chicago’s Rush University Medical College told PBS. “The vast majority of gun violence is not attributable to mental illness.”

“We are not talking about Second Amendment rights or restricting your ability to own a firearm. We are talking about a public health crisis that our Congress has failed to address. This must end,” American Medical Association President David Barbe wrote about the U.S. ignoring it's mental health problem.

Watch Trump blame mental illness for mass shootings below: