Last February, Trump signed a bill making it easier for people with mental illness to buy guns

It did not attract a ton of attention at the time (nothing does these days) but about a year ago on February 28, 2017, Congress passed and Donald Trump signed a law revoking an Obama-era regulatory initiative that made it harder for people with mental illness to buy a gun.

Yet despite this effort to roll back even a very modest effort to restrain the ability of seriously incapacitated people from obtaining deadly weapons, this morning Trump tweeted that there were “so many signs that the Florida shooter was mentally disturbed,” implying that someone should have done something to report him.

But it’s Trump’s party — and Trump himself — who have consistently prevented the federal government from doing anything about this kind of situation. The Obama-era gun regulation wouldn’t have had a massive impact on gun violence in the US since it’s estimated that it would only affect about 75,000 people. And disability rights groups had their own objections to the bill so some liberal groups, including the ACLU, joined with the National Rifle Association in urging Trump to reverse it.

But anything that makes it easier to obtain a gun, the research suggests, will likely worsen gun violence. After all, America already has some of the weakest gun laws in the developed world — and repealing a rule that made it a little tougher for some people to buy a gun likely makes that worse.