The interview is about a new US Sentencing Commission report. See links for more details:

http://reason.com/blog/2017/03/14/new-federal-sentencing-data-shows-a-decl

https://www.washingtonpost.com/news/wonk/wp/2017/03/14/federal-marijuana-convictions-dropped-by-half-under-obama/?utm_term=.a4d123787291