Bob Vander Plaats, the president of the Christian conservative group The Family Leader, is under fire for laughing at a fag joke, the Iowa Independent reported.

Video of Vander Plaats laughing at and complimenting – “Oh shoot, that's pretty good.” – an audience member's off-color joke during a March stop in Audubon, Iowa surfaced on Tuesday.

“You know what my wife says?” an unidentified man is heard saying. “She says: Iowa, the state where you can't smoke a fag, but you can marry one.” (The video is embedded in the right panel of this page.)

While Vander Plaats erupted in laughter, the gay rights group One Iowa wasn't laughing.

The group called on Vander Plaats to apologize in a message to supporters titled Shame on you, Bob!

“Vander Plaats has said he loves all Iowans, and that he is only speaking the truth,” said Troy Price, executive director of One Iowa. “Well, if he is telling the truth when he says that he is not mean-spirited, then he should apologize quickly for his actions.”

The Family Leader is the group behind the much ballyhooed anti-gay marriage pledge rejected by all but two 2012 presidential candidates: Minnesota Rep. Michele Bachmann and former Pennsylvania Senator Rick Santorum.