a sealed wiretap warrant

[Mike Hussey]

Undercover cop to catch a mole from Costello's gang, Billy says to Dignam:

Billy: Disinform. Let it slip to SIU that you have a sealed wiretap warrant...for Costello's apartment. Don't tell anyone in our division, but tell SIU. Flush it down the pipe, see if it comes out on my end. That's what we do first. Narrow it down.

What does "a sealed wiretap" mean?
Source: "The Departed" (a 2006 American crime film directed by Martin Scorsese and written by William Monahan)

 

[GoesStation]

It's a sealed warrant, not a sealed wiretap. The judge has issued a warrant, a legal document authorizing a wiretap, and has sealed it: temporarily made it secret.

 

[Charlie Bernstein]

Mike, have you been using your dictionary? What is unclear about the definitions of sealed and wiretap?

Police need permission from judges to take certain actions, such as wiretapping. The document the permission is written on is called a warrant. It's sealed so no one can see it until it's used.

Billy wants SIU to think he has a warrant to wiretap Costello's apartment.

(Cross-post.)

 

[SoothingDave]

Until after it's used. It would be pointless to tell the person whom you are wiretapping that you have a warrant to wiretap them.

 

[Charlie Bernstein]

Until after it's used. It would be pointless to tell the person whom you are wiretapping that you have a warrant to wiretap them.

Exactly.