Hello Neira,
There is a statute specifically aimed at the expunction of Misd. Larceny – see NC Gen Stat 15A-145. Generally, you have to wait 15 years in order to apply for this expunction.
I'm not aware of any specific statute that would allow you to expunge a simple assault charge and conviction.
Just to be clear, you referenced these as "charges." I am assuming that you were also convicted. If that is NOT the case, and you received dismissals or were found not guilty, that is another matter altogether.
You probably want to talk to an attorney about a possible Motion
for Appropriate Relief – although you probably don't have a statutory
basis for filing this type of motion, sometimes you can get the DA's to
consent if you would have been eligible for a first offender's program,
but didn't avail yourself of the opportunity because you didn't know
about it.
Your last resort could be to apply for a pardon of forgiveness (there are three types of pardons, see my website: http://www.ncexpungement.com)
There is a "bill" or a "proposed" new law pending in the North
Carolina House that may make you eligible for expunction if it passes…
see House Bill 675 (link to NC Legislature site) (link to text of bill). You may want to call your congressman and ask him or her to support this bill.
Feel free to call my office if you need more specific advice. 888.364.2949