I agree whoever handed over the docs may have issues as I stated.
Someone has to assert that a privilege applies or it must be a plainly evident privilege may apply before Mueller or any attorney on his team is obligated to anything. Obviously it would be unlikely all of it would be so bound. Perhaps a case could be made for executive privilege in the case of the president elect but it would have to be argued that there is but one president at a time. As we saw in the case of Nixon and Reagan executive privilege does indeed have limitations.
Mueller as a special counsel acting as prosecutor has different obligations legally than say an attorney not appointed for investigation of an individual or specific group.
It's not a criminal violation for Mueller to ask for private communications. It is not a criminal violation to receive private communications. It may be that information contained in some such communications may be excluded at trial, but that does not necessarily make it fruit of the poisoned tree, nor does it necessarily make any product derived from it poisoned. It may well, but that's a whole lot of arguing before it gets sorted.
