http://wiki.radioreference.com/images/1/12/RadioReference_Response_to_MRA.PDF - please see the bottom of page 2
http://forums.radioreference.com/live-audio-administration/180762-legality-radioreference-live-audio-broadcasts-archives.html - June 2010 - the legality of live scanner audio
http://forums.radioreference.com/virginia-radio-discussion-forum/191875-moral-dilema-2.html - October 2010 - Will online scanning lead to the encryption of all radio traffic?
http://www.justice.gov/usao/eousa/foia_reading_room/usam/title9/crm01066.htm - US Attorney criminal guide - the Radio Act of 1934 was aimed at "communications personnel" ( the people who handled telegrams for Western Union after the Pony Express went out of business )