New US Law Regarding CallerID Spoofing
The US Congress has passed a law making certain types of malicious use of CallerID spoofing a felony. Please refer to the text of the new law for the specifics.
The law exempts law enforcement agencies, so the investigative technique described here remains valid for exempted US agencies. Below is the text describing the LE exemption:
“LAW ENFORCEMENT EXCEPTION.— This section does not prohibit lawfully authorized investigative, protective, or intelligence activity of a law enforcement agency of the United States, a State, or a political subdivision of a State, or of an intelligence agency of the United States, or any activity authorized under chapter 224 of title 18, United States Code.”