At the bottom of the flyer:
"Each indictor listed above is by itself lawful conduct or behavior and may also constitute the exercise of rights guaranteed by the U.S. Constitution."
Don't let pesky details get in the way, JRIC...
This is all about the lawyers' guild wanting to maintain an artificial scarcity of legal options, so that they can keep their fees high. It's why the bar exists, and it's why laws are purposely so obtuse that an everyman cannot interpret and argue them. Lawyers want to maintain the need for 'lawyerly' services, to the detriment of the remainder of the public.
They're probably running Websense, with the Uncategorized category blocked, which is not necessarily a bad idea because sites that are not in the master database could be anything - porn, games, etc. We encounter this all the time with smaller and/or newer sites.