Sessions, who endorsed presumptive GOP presidential nominee Donald TrumpDonald TrumpSix big off-year elections you might be missing Twitter suspends GOP Rep. Banks for misgendering trans health official Meghan McCain to Trump: 'Thanks for the publicity' MORE, criticized Clinton for saying the District of Columbia v. Heller decision, which he said "protects the right of individuals to keep and bear arms," was wrong.
With the death of Supreme Court Justice Antonin Scalia, Sessions said the court is now split, 4-4, in its support of the decision.
"She gets in, she will appoint somebody who changes it, and what that means is it's no longer a personal right to have a gun, but every city, county and state can completely ban firearms in America," he said on "Fox News Sunday."
"This would be the greatest reduction of Second Amendment rights since the founding of the Republic."
Sessions said it was important the American people understand the extent of Clinton's "radical position" on the issue.
Sessions also called the list of potential Supreme Court nominees Trump released last week a "really fine list" of "accomplished" people.