Rioters in Downtown Portland

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No, Machine Guns are not illegal.

Contrary to popular belief, it is perfectly legal for a law-abiding American citizen to own/possess a machine gun (sometimes called a full-auto firearm or automatic weapon).

Of course, there are some restrictions on machine gun ownership/possession for non-government/law enforcement personnel.

For example, a private citizen can lawfully own a machine gun only if:

1. the possessor isn’t a “prohibited person,”
   
2. the full-auto machine gun was made before 1986, and
   
3. their relevant state law does not ban that the firearm (whether banning machine guns outright or any firearm with certain features).
   

As you can see, machine gun possession is regulated based on the person (possessor), the firearm itself (when it was made), and where the firearm is possessed (which state).

Machine gun owners can’t be “prohibited persons.”
Well, to be more accurate, a “prohibit person” can’t lawfully possess a machine gun – ownership is irrelevant.
A “prohibit person” is a class of person defined under federal law who is not allowed to posses firearms nor ammunition (not just full-auto machine guns).
The category “prohibited person” includes anyone who:

• is a felon
  
• has been convicted of any crime punishable by more than a year in prison (whether or not they were ever sentenced to or served a day in prison)
  
• is under indictment for any crime punishable by more than a year in prison
  
• is a fugitive
  
• is an unlawful user of any controlled substance
  
• has been adjudicated as a mental defective
  
• has been committed to a mental institution
  
• is an illegal alien
  
• has a dishonorable discharge from the military
  
• has renounced their U.S. citizenship
  
• is the subject of a restraining order restraining the person from harassing, stalking, or threatening an intimate partner or the child of an intimate partner, or
  
• who has been convicted of a misdemeanor crime of domestic violence
  

There’s a few nuances that you might need to be aware of if you think that any of these apply to you – especially the “convicted of any crime punishable by more than a year,” “unlawful user of a controlled substance,” and “restraining order” provisions.  If you’d like to learn more about these prohibited person categories, see Prohibited Persons / Firearm Possession.
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