So this guy (I can't be bothered to research his name) pleaded guilty to attempting to extort David Letterman. The plea agreement calls for him to serve 6 months in jail. No problem there. It also calls for him to never publish or reveal the information he has about Letterman. Big problem there.
Remember, the fact that this guy was going to write a screenplay about Letterman was not criminal. What made it criminal was his telling Letterman he would publish the screenplay unless Letterman gave him $2 million dollars.
He could have taken the same elements in the screenplay, drafted them into a legal summons & complaint, handed it to Letterman and inform him that "I will sue you for intentional infliction of emotional distress unless you settle with me for $2 million dollars."
Which raises my main point: why does the Manhattan District Attorney's Office care whether this guy publishes this info? Why was it part of the plea agreement?
If the guy publishes something false or defamatory about Letterman, Letterman can sue him for slander or defamation. It's not something that should be a concern of the Manhattan DA's office.
Letterman is a big boy with boatloads of cash. He can handle his own business. The Manhattan DA's used more than enough resources setting up a videotaped dragnet to catch this guy for blackmail/extortion. They didn't need to go further and act as Letterman's private lawyer here.