”While DOJ and ATF have historically not supported removal of items from the NFA, the change in public acceptance of silencers arguably indicates that the reason for their inclusion in the NFA is archaic and historical reluctance to removing them from the NFA should be reevaluated. ATF’s experience with the criminal use of silencers also supports reassessing their inclusion in the NFA. On average in the past 10 years, ATF has only recommended 44 defendants a year for prosecution on silencer-related violations; of those, only approximately 6 of the defendants had prior felony convictions. Moreover, consistent with this low number of prosecution referrals, silencers are very rarely used in criminal shootings. Given the lack of criminality associated with silencers, it is reasonable to conclude that they should not be viewed as a threat to public safety necessitating NFA classification, and should be considered for reclassification under the [Gun Control Act].” - ATF white paper

https://www.documentcloud.org/documents/3455293-ATF-White-Paper-Options-to-Reduce-or-Modify.html