If you ever receive a phone call from your local prison on your house phone and the operator tells you to press 1 to get a collect call, don’t accept it (unless your buddy is arrested on regular basis and you know he always calls). Many victims accept these collect calls because they don’t know who might be on the other side.
How does this scam work? Whenever allowed to make phone calls, real inmates dial random numbers until they find somebody willing to help. As soon as the victims answer, the scammer comes in with a quick apology for disturbing them followed by an emotional short story, such as being thrown in jail because he beat up a guy who assaulted his daughter, an hour ago.
The prisoner will ask the victim to call a number where supposedly his daughter is, to check out on her. He will say that the number is impossible to reach from the prison he is in, or that they are not allowed to call cell phones. Several people fall for this scam as they think they are doing a good deed.
In reality, what victims do when dialing the number provided is just… call-forwarding their own telephone lines. This way, after getting you to forward the number, the scammer can call anywhere he wants, without being charged.
How to avoid: check the forwarding code in your country and make sure you never use that when required to by someone else.