Del Bianco said commercial spoofing services cooperate with law enforcement subpoenas. He said investigators are pleased when crooks use commercial spoofing services instead of their own spoofing technology, because the spoofing companies keep complete records of every call and make those records available to authorities.
Del Bianco said his clients offered to block bank phone numbers from their services, so callers would not be able to spoof them. But banks did not want to provide the numbers, so the effort stalled.
ABC News asked Del Bianco to explain the legitimate purpose of the voice-changing feature, which allows callers to disguise their voices and he said, "There may be none," but added that it's included as on option because "it's a part of the software."
ABC News tried out a spoofing service we found online. For $10 we purchased an hour of talk time. We then dialed the spoofing company's toll free number.
First, a recorded message prompted us to enter the number we wanted to call. Then another prompt allowed us to enter the number we wanted to appear to be calling from. A third message asked us if we wanted to disguise our voice. We then called co-workers and, sure enough, we were able to make it look like we were calling from a major national bank, the Internal Revenue Service, even the CIA.
When somebody has the ability to alter the number that comes up on caller-ID, there's the potential they will abuse that power. Scammers who spoof numbers are usually calling people up and fishing around for personal financial information they can use to steal their identities, known as "Phone Phishing."
Every year, millions of Americans fall victim to phishing scams over the phone and online. And e-mail addresses can be "spoofed" too! There are several ways to protect yourself:
First and foremost, never give out financial information over the phone unless you initiated the call.
Keep in mind that your bank already knows your account number, etc., so would not be asking for it.
Be wary of callers who ask for "confirmation" of personal information, such as social security numbers, credit card numbers and credit card security codes.
Don't call phone numbers that are listed in e-mail messages or links. Instead, look up the number yourself online or go low tech and find it on your statement.
Ask the callers if you may phone back with the information they have asked for, then call the institution directly to confirm.
If you have already given your information to someone over the phone, contact the real company directly right away to alert them that you may have been scammed.
Finally, monitor your bank accounts and credit reports to be aware of any suspicious activity.
You can find additional information about spoofing and phishing here:
The Federal Trade Commission is the nation's identity theft clearinghouse: http://www.ftc.gov/bcp/edu/microsites/idtheft/
The National Consumers League is a nonprofit organization that tracks fraud: http://www.fraud.org/tips/internet/phishing.htm
To order your free credit report and check it for suspicious activity: www.annualcreditreport.com
ABC News' Kim Berryman contributed to this report.