We are a nation of laws, and even in tough times we consider our commitment to the rule of law to define us. Even if someone is saying something we don't like, we respect their First Amendment right to say it. Even if we think someone is guilty, they are still entitled to Fourth Amendment protections against unreasonable search and seizure and Sixth Amendment rights to a fair trial. This commitment may be why it's fun to imagine a world where we don't follow the law for a little while.
If you haven't seen the movies by now, you've probably seen a preview or three, or heard "The Purge" was coming to your town for real. The basic premise of the film (and its two sequels) is that, for 12 straight hours per year, all crime is legal and all emergency services will be unavailable. Billed as a civic tradition in the movie's timeline, it has the effect of reducing crime and unemployment. Beyond the wistful, "wouldn't it be fun to run around and do whatever you want for a day" fantasy, could suspending all laws temporarily even be legal?