CHICAGO (CBS) — Before Nicholas Cruz killed 17 people at Florida’s Parkland High School last year he posted images of guns, bullets and a dead frog on Instagram. And before former Marine Ian David Long gunned down 12 last year at a California bar he posted on Facebook, “I hope people call me insane.”

“This is something my community is demanding action on,” said Rep. Daniel Didech (D-Buffalo Grove).

That’s why Didech is proposing gun buyers reveal their public social media accounts to Illinois police before they’re approved for a firearm license.

“A lot of people who are having mental health issues will often post on their social media pages that they’re about to hurt themselves or others,” Didech said. “We need to give those people the help they need.”

Pro-gun groups are outraged.

“When people look at this everyone who has a Facebook account or email account or Twitter account will be incensed or should be,” said Richard Pearson with the Illinois State Rifle Association.

But the ACLU is opposed as well.

Rebecca Glenberg with ACLU Illinois says the bill “doesn’t say anything about how that list will be retained and for how long and what uses it might be put to.”

The first amendment group worries police scanning social media may show bias.

“A person’s political beliefs, a person’s religious beliefs, things that should not play a part in whether someone gets a FOID card,” Glenberg said.

But Didech isn’t deterred.

“It gives Illinois State Police additional tools to make sure that dangerous weapons aren’t getting into the hands of dangerous people,” he said.

Didech says his bill is a less intrusive version of a similar measure that’s been proposed in New York state. That version allows police to recover a gun license applicant’s entire browsing history. Even Didech says that goes too far.