 Beginning in 1979 , the Ethics in Government Act of 1978 required federal officials , including the justices , to file annual disclosures of their income and assets . These disclosures provide a snapshot into the wealth of the justices , reported within broad ranges , from year to year since 1979 . In the first such set of disclosures , only two justices were revealed to be millionaires : Potter Stewart and Lewis F. Powell , with Chief Justice Warren Burger coming in third with about $ 600 @,@ 000 in holdings . The least wealthy Justice was Thurgood Marshall . 
