Question: If I get my juvenile record expunged, can I then state the crime wasn't committed -(for example: on an application)?; If not, what good is it to expunge them?
Answer: Be careful with this topic! A crime can be erased from your file's history [or taken off of your 'record'], but a specific act you have taken cannot be erased from your own history. Once you commit an ACT [in your example, a crime], you can never erase that ACT from your past [in your example, say that you did not commit a crime]. HOWEVER, when your file is 'expunged', you will no longer have a record of your crime in your file.
Arizona Law (A.R.S. § 8-349) states the rule on how to destroy a juvenile's court records, or 'expunging' one's file. If you satisfy all of the requirements of this Law [be at least 19 years of age, not have been convicted of a felony offense, there are no criminal charges pending, and completing all of the terms and conditions of court ordered probation] then you could get your file erased. What this means is you have no criminal history - so when you are filling out an application and you get to a question on your criminal history - you can honestly say that you don't have a criminal history. [Many times the question is phrased around the commission of a crime as an adult, in any event.] 'Expunging' is a benefit, then, because it allows you to clean up your criminal past and start fresh without a criminal past.
When someone asks you if you've committed a crime, you can answer that you have no criminal history. That would be true. But again - the actual act never disappears.