Is your friend able to come out to Utah personally?
If so, he can take care of this issue by himself. All he needs to do is go to the Bureau of Criminal Investigations (BCI) and fill out
this eligibility form along with a $50 application fee. If his charge is eligible for expungement, then he'll be notified by snail mail a few days after his application is received. The kicker here is that once he receives his eligibility papers, he only has a small window of time to care of it; this window is I believe 30 days, maybe 90 days. In his eligibility packet, he'll be given a list of all charges available for expungement (these will include traffic citations) and a list of courts he can visit to have them expunged. There's typically a $100 fee per criminal charge that will accompany the expungement and each charge to be expunged has to be done so at the court it was originally processed through and he, or a person representing him, must appear personally to have the charge removed.
If he only has one charge, he's looking at about $100 and the $50 application fee for the eligibility form. If he goes through an attorney, the average fees start out at around $5,000. I could be wrong about the attorney's fees, but that's what I was quoted when I tried to do this. I ended up doing mine myself and I wasted about 3 days of work and lost wages, but took care of mine for well below the attorney's price.