CNN’s Anderson Cooper gave a writer at a conservative website a lesson in reporting Thursday night.

The Daily Caller’s Laura Donovan attacked Cooper Thursday for a segment he did mocking 16-year-old singer Courtney Alexis marriage to 51-year-old actor Doug Hutchison.

Apparently it wasn’t clear to Donovan that Cooper was being sarcastic when he jokingly referred to people objecting to the age disparity as “romance haters” in his Wednesday “RidicuList” segment.

“Unlike much of the population, CNN anchor Anderson Cooper isn’t repulsed by the Las Vegas nuptials,” Donovan wrote.

“I bet at The Daily Caller, if someone tells a knock knock joke everyone runs to the door and waits to see who comes in,” Cooper said Thursday.

After outraged Cooper fans wrote the conservative website explaining that he had been joking, editors had to correct her story and she responded on Twitter.

“I knew it was sarcastic!” she claimed. “I said in my story that he took ‘sarcastic jabs.’ Guess I could have been clearer.”

“Clearer than a completely misleading headline followed by a completely misleading story?” Cooper asked. “Come on, Laura. Don’t be so hard on yourself.”

Then the CNN host offered a few words of advice: “You’re only 22 years old. You wrote for your college newspaper and you have a blog about guys who hit on you or something. I couldn’t really get into it. I know when you’re starting out in today’s snide internet culture you want to make a name for yourself. I know that attacking others is an easy way to do that. Maybe you want to prove you’re ideologically on the right side. In the future, don’t be so quick to attack. Make sure you research what you write. That way your editors don’t step in and rewrite your inaccurate stories.”

The Daily Caller’s Jim Treacher responded with a series of unfunny, gay-baiting knock knock jokes about Cooper.

This video is from CNN’s Anderson Cooper 360, broadcast June 23, 2011.

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