Riley is the fourth suspect to be convicted in the death. Albert was beaten to death in September 2009. The videotaped attacked garnered national attention.
Riley struck Albert with a wooden board during the attack. He had argued that he was only trying to protect his younger brother.
Three others have been found guilty in the case: Silvonus Shannon, who received 32 years in prison for murder; Eric Carson, 18, who received 26 years in prison after pleading guilty; and a juvenile who was found delinquent.
A fifth suspect- Lapoleon Colbert- has not been tried.
