The Freedom of Information Act
It was mailed to NBC, and they turned it over to the police.
After its existence became known, if its content hadn't been released, other media have the right to petition the courts for its immediate release as a newsworthy item. NBC didn't ask for the tape; why should they have to pay their lawyers to keep it off the air?
If it's going to be released anyway, inevitably, NBC at least got to cut it for air for its debut. If FOX had gotten it, do you think they might have shown the whole thing?
