Louis C.K. made a big confession on Sunday: He really did steal the scales from his junior high school in Massachusetts many years ago.

The situation became fodder for a flashback storyline in an episode of FX’s “Louie” last year. C.K. told reporters at the Television Critics Assn. press tour that he had always felt bad about the incident because one of his teachers defended him at the time when he denied stealing the science-lab scales.

And just as it played out in the episode, the school’s principal knew he did it but left him off the hook.

“I sold them for drugs,” he said. “I’d been sitting on this story a long time.” To compound his guilt, the teacher who defended him emailed him recently to say how proud she was of his success. He confessed to her in his response and got an “I’m disappointed in you” reply.

“She was a great teacher,” C.K. said. “I had every advantage when I was a kid. I grew up in Newton, Mass., a nice town. I just got high — my working single mother, I f—– her life up. I was a terrible kid.”

C.K. said that the upcoming fifth season would likely be lighter and funnier than season four, which many critics noted took a darker, more serious turn.

“This season is more laugh-centric funny than season four,” he said. “I had a very playful and goofy feeing going into this season.”

He addressed another episode of season four that stirred controversy last year with a scene that some said suggested that Pamela Adlon’s character was date-raped by Louie after being reluctant to have sex. C.K. and Adlon said they were surprised by the reaction as the scene was meant to be funny.

“She wasn’t scared in the scene, she was annoyed. She was never in danger,” he said.

C.K. said he was “fascinated” by the reactions people have to the show, and he admitted he reads a lot of commentary about the show. But he does not respond to avoid going around in circles over past material.

“If you become part of your own discussion it’s kind of crazy,” he said.