Law & Order, Season 19

[Darvey has holed up in the Iranian Embassy, making it legally impossible for him to be arrested]

Cutter:
So a killer sits in there eating caviar while we do... nothing?

Barsett:
We're trying to negotiate the Iranians out of building nuclear weapons. We don't need to be distracted by a common criminal.

Lt. Van Buren:
Common murderer. Darvey left his suitcase in the cab with a gun inside. Ballistics are a near-perfect match.

Barsett:
I'm sorry. We have to respect the treaty.

McCoy:
And if we don't, what are they going to do? Invade our embassy in Iran and take 50 hostages? Oh, wait - they already did that.