Some information for you on this.. The DNC isn't a call blocker and can not protect you from the illegal callers, extortion scammers, foreign country's and frauds. Criminals do not obey laws simply said. They use spoofed numbers which make it hard to track them down.. it takes time to do this and many subpoenas for call records.
http://800notes.com/forum/ta-e433d104c45c9b7/ ... oofed-caller-id
http://800notes.com/forum/ta-c3355f57425c0d5/ ... alls-to-the-fcc
http://consumerist.com/2015/07/22/45-attorney ... lock-robocalls/
http://800notes.com/forum/ta-c5c7e69f0670886/ ... -spoofing-calls
http://800notes.com/forum/ta-c46b87360deec56/ ... -unwanted-calls
https://www.ftc.gov/news-events/press-release ... ainst-political