Washington (CNN) Attorney General Jeff Sessions said he should have brought up presumption of innocence earlier this week when he spoke to a group of conservative high schoolers chanting "Lock her up!" in reference to Hillary Clinton.

Sessions, the nation's top law enforcement officer, caught flak on Tuesday afte r he uttered the phrase during remarks promoting free speech and conservative principles at conservative group Turning Point USA's high school leadership summit in Washington.

"Lock her up," Sessions said, chuckling at the brief interruption from the audience as the chant then grew louder. "I heard that a long time over the last campaign."

Sessions, speaking at a press conference in Boston on Thursday, said that he should have advised the students to presume individuals are innocent until proven guilty.

"Well, I met with a group of enthusiastic high school students ... and they spontaneously broke into that chant. I perhaps should have taken a moment to advise them on the fact that, the things I mentioned today -- presumed innocent until cases are made," Sessions said, smiling throughout his answer. "It was a great event to be with those kids."

Read More