This is a good start, but with Internet VOIP spoofing companies like spoofcard.com it will be hard to enforce. The following report from WPTV explains.

If you think caller ID protects you from fielding all unwanted calls - think again.

A technology known as caller ID "spoofing" allows anyone to essentially sabotage the caller ID function on a phone. 

Websites such as spoofcard.com allow you to place a call pretending to be someone else.  The recipient will see the number you choose on his or her caller ID.  And when the person picks up the phone, the program allows you to disguise your voice, calling as a woman or a man.

The technology has a long history of use in practical jokes.  According
to the Associated Press, this year in Delaware a telemarketer called families using the number: 867-5309.  You may remember that number from the 1980's hit - "867-5309/Jenny."

But St. Lucie County sheriff Ken Mascara says the "spoofing" technology is no joke when it's used for fraud: people posing as a bank or the IRS.

"The main reason they attempt to defraud a person is to get personal information for identity theft or to defraud them of their life savings," says Mascara.

Working with the Florida Sheriff's Association, Mascara directed his sheriff's office attorney to write the "Caller ID Anti-spoofing Act."  It's a bill which has now become law in Florida.  It makes it a crime to use spoofing technology with the intent to defraud.

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