No. You are making the argument that because you were investing in the co-op that the attorney for the co-op then becomes your attorney. That's not a good argument. If you buy stock of Google, Apple, GM or whatever other company you can think of that does not make their lawyers now your lawyers too. You never retained this lawyer to give you legal advise and representation. You weren't looking to him to provide you legal advise. Indeed, you knew he was representing the seller (Dick) in this transaction and thus was not representing you. You were not his client and he was not giving you legal advise or representation. He may well be liable as a party to the fraud (assuming there was fraud) but you won't succeed in a legal malpractice claim against him.