So, you want to keep people who "shouldn't have guns" from having them?
Releasing balloons can lead to felony charges. (h/t) Instapundit)
That's a 3rd degree felony, which could lead to a 5 year prison sentence. And as the federal law stands, any crime punishable by more than 1 year federal (or 2 years state, if a misdemeanor) gets you on the "prohibited person" class. You don't have to spend a second in jail or in prison, you just have to be convicted of a crime that could have gotten you over a year (or 2 years if a state misdemeanor) in prison.
Won't you be glad when this flagrant balloon releaser is not able to legally purchase or possess a firearm or ammunition? Now we just need to track down that criminal mastermind Jules Verne...
Might I suggest reading Absolutism 301: Felons? Just so when you hear someone say that background checks are necessary to prevent felons from acquiring firearms you know exactly how asinine that argument is.