Sen. Marco RubioMarco Antonio RubioRepublicans think Trump is losing trade war The Hill's 12:30 Report — Sponsored by Delta Air Lines — Trump meets South Korean leader as questions linger about summit with North Senators demand answers on Trump’s ZTE deal MORE (R-Fla.) on Sunday said he was “skeptical” of a bipartisan measure to expand background checks on gun sales, saying the nation was ignoring the larger issue of “violence.”

“I haven't read it in totality. But I can tell you this, I am very skeptical of any plan that deals with the Second Amendment, because invariably, these gun laws end up impeding on the rights of people to bear arms who are law abiding and do nothing to keep criminals from buying them,” said Rubio on “Fox News Sunday.” “Criminals don't care what the law is.”

The Florida lawmaker appeared on all five Sunday morning shows in a public defense of an emerging immigration bill he is crafting as a member of the Senate’s ‘Gang of Eight.”

But Rubio also faced questions about his vote to filibuster the Senate’s gun control bill last Thursday.

The Senate voted 68-31 to allow debate on a gun control bill and is expected to vote on the background check compromise as an amendment this week. That measure crafted by Sens. Joe ManchinJoseph (Joe) ManchinOvernight Finance: House sends Dodd-Frank rollbacks to Trump | What's in the bill | Trump says there is 'no deal' to help ZTE | Panel approves bill to toughen foreign investment reviews House votes to ease regulation of banks, sending bill to Trump Senators demand answers on Trump’s ZTE deal MORE (D-W.Va.) and Pat Toomey (R-Pa.) would expand background checks to all gun show and internet sales, but exclude transfers between family members.

Rubio said he feared the momentum to enact more gun control would result in ineffective measures and prevent a larger, needed debate on violence.

“I think the bigger point is, we're missing a golden opportunity here. We're focusing so much on guns. We should be focused on violence. Violence is the problem,” he said.

“Guns are what they're using to commit violence but violence is the central problem. And no one -- they all want to talk about what they're using, no one wants to talk about what is happening.”

Rubio defended votes as a member of Florida’s state legislature in favor of background checks, arguing that those covered individuals who sought to carry concealed weapons. 

“Those background checks in Florida are for people that have concealed weapons permits. For example, if you have a concealed weapons permit, you do a background check. I have no problem with that,” he said. “But are they going to honor that in all 50 states? If someone goes to another state to buy a gun, do I have to undergo another background check or will my concealed weapons permit be de facto proof that I am not a criminal? These are the sorts of things I hope we'll talk about.”