CSPAN Public Affairs October 21, 2012
I think in first of all i should say whether a land line or cell phone, you are just as likely to be a to victim of robocalls. That in and of itself does not protect you. There is some hope beyond the items steve mentioned for reasons completely unrelated to robocalls, the federal Communication Commission simply has mandated cell phone carriers do much better job of passing on valid signaling and numbering information. That may well also be helpful in some circumstances to provide traceable info...
Source: archive.org