Letterman disclosed the office relationships in telling viewers of what authorities say is a plot devised by longtime CBS News producer Robert Halderman (known as Joe), 51, to extort $2 million from the late-night star.
Halderman, posted $200,000 bond and was released. The veteran producer of real-life crime program "48 Hours Mystery" has been suspended by CBS News.
His lawyer, Gerald Shargel, urged the public not to rush to judgment on Halderman, during an "Early Show" interview Monday.
Now, the identities of two women said to have had affairs with the late night star have come to light.
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The New York Times reports that, "A central figure in the case -- one of the women who did have a sexual relationship with Mr. Letterman, according to representatives of the show -- is Mr. Letterman's longtime personal assistant, Stephanie Birkitt, 34, who also often appeared on the air. The sexual relationships had ended before Mr. Letterman was married in March, a Worldwide Pants (Letterman's company) executive said."
The Times adds that Halderman lived with Birkitt in Connecticut until last month.
Letterman, 62, is married to his longtime girlfriend, Regina Lasko. They have a six-year-old son.
A second supposed alleged romance was with Holly Hester, a "Late Show" intern in the 1990's.
She told celebrity Web site TMZ.com, "I was madly in love with him at the time and would have married him. He was hilarious."
TMZ adds, "Hester says Dave ended it after a year -- she says he told her the age span was just too great."
Sunday's New York Post reported that Letterman's office in the Ed Sullivan Theater, off -imits except to a select few, had a bedroom with a pull-out couch. Sources confirm the couch in his office, but deny there is a private bedroom.
Meanwhile, many of Halderman's co-workers are expressing shock over the accusations against him.
Former CBS News Medical Correspondent Dr. Bob Arnot says, "Joe has been one of my best friends. He's been one of the most upright, honest, straight-forward, honorable human beings that I've ever known."