(Covers information from the D.C. comics)
Earl was an Umbrella security guard employed one of the company's storage warehouses.
He and another guard were on duty the night Dexter Whitlam sneaked in. Although they chased after Dexter, they decided that since he was only a teenager there was no point in pursuing him. Afterwards, they discovered that one of the G-virus samples was missing. Failing to leap to the conclusion that Dexter had taken it, Earl and his partner elected not to inform their superiors.
Sometime later, a pair of Umbrella agents on a routine inspection of the facility noticed the missing sample. The senior agent interrogated both guards, and a visibly fearful Earl admitted that they had seen a teenage boy in the warehouse, but let him go. The agent thanked them for their help... then ordered his partner to kill them.