Washington types loosened their ties and poked fun at one of TV's biggest names Wednesday night at the Spina Bifida Association of America annual roast: "NBC Nightly News" anchor Tom Brokaw.

The usually respected and respectable Brokaw, 62, told PEOPLE before the barbs started flying that "it's only fair" to let the politicians he reports on get their chance to rake him over the coals. Besides, he said, "I get the last word."

NBC's parent company, General Electric, sponsored the event, prompting Brokaw to inform the audience: "We encourage you to eat up and drink up. This is all on (former CEO) Jack Welch's expense account" -- the excesses of which Brokaw and nearly every other news outlet has been recently reporting.

"I really am deeply flattered and privileged to be here tonight," Brokaw also said, "especially when I realize that for $260,000 and (former ImClone chief) Sam Waksal's cell phone number, you could have had Martha Stewart in here on the dais."

On a more serious note, Brokaw said it was his pleasure to participate in the benefit because of his friends Al Hunt, of the Wall Street Journal, and CNN anchor Judy Woodruff. The couple founded the annual roast 14 years ago to help their son and the 70,000 other Americans who have Spina Bifida, the most common birth defect that results in a permanent disability in the United States.

"It's a great tribute to them," the NBC anchor told PEOPLE, "and the least that I can do is show up one night a year and help them out."