Superior Court Senior Judge William M. Fleming Jr. denied the bond, citing Sullivan as a threat to public safety.
Sullivan, 19, is facing charges of armed robbery and possession of a firearm during the commission of a crime for involvement in the Aug. 27 armed robbery of a 38-year-old North Augusta man.
The North Augustan told police he responded to a Craigslist ad for an Apple iPhone and was robbed of $320 and his smartphone at gunpoint after he arrived for the sale.
Sullivan was also charged with involuntary manslaughter for a slaying on Nov. 11. According to police, Sullivan fatally shot his “very close friend” Delarrion Smith, 18, while horseplaying with a .45-caliber pistol.