The US Supreme Court has lifted a ban bump stocks, the rapid-fire gun accessory used in America's deadliest mass shooting.

.The US Supreme Court has lifted a ban bump stocks, the rapid-fire gun accessory used in America's deadliest mass shooting.

In a decision on Friday, the court said the government did not have the right to ban the accessories. The Trump administration banned bump stocks after they were used in a shooting that killed almost 60 people at a concert in Las Vegas in 2017.

But a Texas gun shop owner who challenged the ban said the government went too far in defining the accessories as machine guns, which are illegal under federal law, and took his fight all the way to America's highest court. The court said a semi-automatic rifle with an attachment does not qualify as a machine gun under federal law.

The Supreme Court’s opinion, written by conservative Justice Clarence Thomas, said the Bureau of Alcohol Tobacco and Firearms had “exceeded” its authority.

The court, quoting part of the legal definition of machine guns, said rifles with a bump stock "cannot fire more than one shot 'by a single function of the trigger', and even if they could, they would not do so 'automatically'".