A spokeswoman for the agency, Lisa Eimiller, said the decision was not a response to a request from Pasadena Police Chief Phillip Sanchez, the Los Angeles Times reported.
"The FBI is assessing the incident involving the Pasadena Police Department on March 24, 2012, which resulted in the death of Kendrec McDade. The FBI will seek to determine whether a violation of federal civil rights law was a factor," the agency said in a statement.
McDade, 19, was shot when two Pasadena officers responded to a call from a man who said his car was being broken into. McDade's death is also being investigated by local police, the Los Angeles County prosecutor and another county agency.
Pasadena police investigated the man who made the 911 call on suspicion of involuntary manslaughter, saying he might have caused McDade's death by falsely telling police he had a gun. The prosecutor has not filed criminal charges.