Los Angeles's justice department is scrutinizing certain investment transactions of public pension funds, including Calpers, the Wall Street Journal said, citing people familiar with the matter.
Federal prosecutors are looking at whether potentially illegal payments were made to influence decisions on where to invest public pension fund money, the newspaper said.
However, the investments under scrutiny are not very significant for Calpers, the $200 billion California Public Employees' Retirement Fund, the Journal said.
A Calpers spokeswoman told the paper that she is not aware of any federal criminal investigations scrutinizing the fund's investments.
Federal sleuths around the country have been trying to determine whether public officials accepted illegal inducements from money managers seeking to invest in pension funds, the newspaper said.
Calpers, the nation's largest pension fund, could not be immediately reached for comment by Reuters outside regular U.S. business hours.
(Reporting by Sakthi Prasad in Bangalore; Editing by Rupert Winchester)