Re: Author is clueless
They don't know who the call is actually from (as CID is trivial to spoof), but they do know where the call comes from (the previous hop in the call delivery). It's a pain in the ass to track a call down, and requires cooperation from the other carriers, who may not want to help prosecute their customers. They don't really care where the call originates, as they don't charge the caller, they charge the previous hop in the chain.
What would ACTUALLY help is making changes to the POTS system so that call setup includes more detailed and accurate caller info, and requiring carriers to globally block calls that are known to be bad. Also good would be requiring auto-blocking of calls with obviously spoofed CIDs (an incoming international call with a New Jersey area code), or that are anonymous.