He should face some legal ramifications for gun charges.

See I say no at this time. That would be hypocritical:

• He was a minor, thus per WI law not allowed to open carry. Ok, put him into the juvenile system for punishment. But then equally, he is in that system for the homicides and leaves it at age 18 with a clean record.

Or

• Prosecute him as an Adult for homicide.
  

They chose the later, so if he is an adult, then he can legally open carry in WI. Sorry, we can't pick and choose laws. I get why around the age of 18 (16-20) we try to look at someone's emotional and intelligence to decide if they are a minor or an adult. But once you determine what some is, then you can't flip back. Some mentally disabled get classified as a minor at any age, they require legal guardianship their whole lives.