If you are telling me that your grandson pled guilty only to an assault but that a charge that was dismissed or never prosecuted still shows as an arrest on his RAP sheet, it would appear that he would be eligible for an expungement
of that charge under South Carolina law.
You can see the South Carolina law on this below:SECTION 17-1-40. Destruction of records where charges dismissed; fee; exception; promulgation of regulations.
(A) A person who after being charged with a criminal
offense and the charge is discharged, proceedings against the person are dismissed, or the person is found not guilty of the charge, the arrest and booking record, files, mug shots, and fingerprints of the person must be destroyed and no evidence of the record pertaining to the charge may be retained by any municipal, county, or state law enforcement agency.
Provided, however, that local and state detention and correctional facilities may retain booking records, identifying documentation and materials, and other institutional reports and files under seal, on all persons who have been processed, detained, or incarcerated, for a period not to exceed three years from the date of the expungement order to manage their statistical and professional information needs and, where necessary, to defend such facilities during litigation proceedings except when an action, complaint
, or inquiry has been initiated. Information retained by a local or state detention or correctional facility as permitted under this section after an expungement order has been issued is not a public document and is exempt from disclosure. Such information only may be disclosed by judicial order, pursuant to a subpoena filed in a civil action, or as needed during litigation proceedings. A person who otherwise intentionally retains the arrest and booking record, files, mug shots, fingerprints, or any evidence of the record pertaining to a charge discharged or dismissed pursuant to this section is guilty of contempt of court
This link will tell you generally what SC will require to get this off of your son's record and where to get the form. (See link
and scroll down to section 4) No lawyer is required to get an expungement but if he's not comfortable with do it yourself lawyering there are lawyers who specialize in this and he might have a better chance with an expungement lawyer than if he does this for himself.