ESPN, citing unidentified sources close to the investigation, reported last week that MLB impeded the Florida investigation.
"MLB investigators knowingly purchased stolen documents in their quest to allow Commissioner Selig to act, for the first time, as if he was tough on PED use in baseball despite striking a cooperation deal with Anthony Bosch who MLB knows is under federal investigation for providing steroids to minors," Jordan Siev, one of Rodriguez's lawyers, said in a statement.
MLB has repeatedly denied the accusation.
"The truth continues to be that we did not knowingly purchase stolen documents and there is an active police investigation to determine if the documents were in fact stolen," the commissioner's office said in a statement.