The former "48 Hours Mystery" producer is expected to start his six-month term Tuesday after admitting to the shakedown plot in March. He pleaded guilty to attempted grand larceny.
Halderman threatened to ravage Letterman's congenial, clean-cut image by revealing the late-night TV icon's office affairs.
Instead, Letterman blunted the $2 million blackmail threat by confessing on his show. His viewership hasn't suffered.
But celebrity lawyers and image-makers say it's unclear whether the case will function as a cautionary tale that deters future shakedowns. They say many stars would rather handle such matters privately than press charges that would air their dirty laundry.
