Your statement appears to be a mischaracterization of the situation in the article. The person holding the paper was told he would be arrested if and only if he

Your statement appears to be a mischaracterization of the situation in the article. The person holding the paper was told he would be arrested if and only if he wrote a specific phrase on it. Not that being arrested for holding a sign with a statement is any better, but it definitely was not "illegal to hold blank paper"