There are a huge number of issues you might tackle, but one, which is referred to in the paper, is the phenomenon that police and security agencies call “going dark”, when the activities of would-be criminals or would-be terrorists are so technically encrypted from beginning to end that there is no ability, or very limited ability, to detect the activities of those who would pose a threat to public safety or national security. That issue—
On October 6th, 2016. See this statement in context.