Hi. New to the forum, but have been following along. Wanted to clear this up. 6th amendment right to counsel is offense specific and attaches once charged; once invoked, defendant may not be questioned in regard to the offense with which he has been charged. 5th amendment privilege against self-incrimination gives basis for the Miranda Rule. Miranda is not offense specific, and truly, anything said can be used against the one questioned; Miranda rights are required whenever an individual is in custody, but not before. Thus, any voluntary statements made to police or media by McD will not be excluded as "fruit of the poisonous tree." Further, police may question McD after Mirandizing him on any offense, but he may, of course, invoke his right to counsel or to remain silent (which I would assume he'd do immediately as a law student). Even if police were to violate Miranda, if McD made some sort of admission, it could come in as evidence in a subsequent trial, not substantively, but at least for impeachment purposes.
That being said, it is my suspicion McD has not given the police any sort of voluntary information after the initial charges for burglary were filed. I can't imagine he or his lawyer would want anything to do with questions regarding the murder investigation.
I do find all the run-around with conflict of interest quite interesting, however. I am not familiar with Georgia Rules of Professional Conduct, but I find the delay quite odd.
In re: FBI involvement so quickly - Lauren's family, being from Maryland and so close to DC, and seemingly being involved in the community up there, perhaps has a friend or relative that works for the FBI and facilitated the immediate involvement. Just a thought, only my opinion of course.