Kerner also wrote for Opera News, Musical America, and Travel + Leisure.
Born in Somerville, Massachusetts, Kerner studied at Tufts University and Boston College. He wrote for Women's Wear Daily before moving to the Voice in 1955, the year it was founded. He wrote for the paper until 2004.
According to Opera News, Kerner won two ASCAP/Deems Taylor Awards and a letter of distinction from the American Music Center.
In his obituary, Opera News editor F. Paul Driscoll wrote, "Although Leighton's critical standards were shaped by long and distinguished service in his chosen field—he was a sharp-eyed witness to all of the most important events in the musical life of New York for a half-century and the range of his knowledge was staggering—he never lost the ability to be excited by a new singer, a new composer, or a new piece of music."