Bump stocks — the gun add-ons that can dramatically increase their rate of fire — are now officially illegal in the U.S., after a Trump administration ban took effect Tuesday. Anyone selling or owning bump stocks could face up to 10 years in federal prison and a fine of $250,000 for each violation.

Chief Justice John Roberts declined to hear an appeal from gun makers on the new ban Tuesday, allowing it to remain in place. A separate appeal that seeks a stay on enforcing the ban is before Justice Sonia Sotomayor.

Updated at 3:20 p.m.

The first of more than 1,600 lawsuits pending against Purdue Pharma, the maker of the opioid OxyContin, has been settled.

The drugmaker and members of the Sackler family, which owns Purdue, have agreed to pay $270 million to fund addiction research and treatment in Oklahoma and pay legal fees.

Oklahoma Attorney General Mike Hunter filed suit two years ago alleging Purdue helped ignite the opioid crisis with aggressive marketing of the blockbuster drug OxyContin and deceptive claims that downplayed the dangers of addiction.

The House of Representatives failed to override President Trump's veto on a congressional resolution blocking his national emergency declaration. That executive proclamation paved the way for the administration to spend billions of dollars to construct a barrier along the Southwest border between the U.S. and Mexico after Congress refused to approve the full amount the White House demanded last year.

The vote was 248-181, falling short of the two-thirds majority needed. Only 14 Republicans joined Democrats to vote to overrule the president.

Updated at 1:40 p.m. ET

The assertion by Attorney General William Barr that special counsel Robert Mueller found the Trump campaign did not conspire with the Russian government in 2016 removes, for now, a major focus of Democrats' messaging.

But it has also given them an opening to turn to an issue they believe is more important to many voters anyway: health care.

Updated at 1:30 p.m. ET

In a significant shift, the Trump administration says the entirety of the Affordable Care Act should be struck down in the courts. Previously, the administration had pushed to remove the law's protections for people with pre-existing conditions but had not argued in court that the whole law should be struck down.