Authorities on Wednesday had tentatively identified the body as 29-year-old Brian Reed, who jumped into the river about 30 miles northwest of New Orleans after an encounter with a sheriff's deputy on Jan. 7.
The autopsy Thursday by the Jefferson Parish coroner's office confirmed his identity and found the preliminary cause of death to be accidental drowning.
Ed Reed says his brother was suffering from mental issues when he ran away from a deputy who tried to question him about driving another brother's car without authorization.
(This version CORRECTS APNewsNow. Corrects Brian Reed's age to 29 per change from police. This story is part of AP's general news and sports services.)