From Papers We Love. The paper that caught my attention is is Keys Under Doormats a paper published in November of 2015 that was co-authored by Susan Landau, Peter G. Neumann, Whitfield Diffie, et. al. paper 
Other papers that enter into this dicussion are: - National Security on the Line, May 2006 - The Real National-Security Needs for VoIP, November 2005 - Codes, Keys and Conflicts: Issues in U.S. Crypto Policy, June 1994
We discussed the Clipper chip and Microsoft's trusted computing.
Executive summary in 2015. This paper is focused on the pentagon of the US, UK, CN, AUS and New Zealand and raised serious concerns ahead of the Snowdon revelations.
To put this context the US telecoms is no longer a regulated industry under tittle two of the net neutrality act. Meaning the opportunity to do surveillance is increased, but government no longer has guaranteed backdoors to do so. FBIsite
Brings up: 'Exceptional Circumstances' can lead to exceptional access vs Bill of Rights wikipedia
ToDo: The fed.wiki security pod may want to re-read this paper, fork and make corrections to my summary reprise of the PWL presentation.