I think you're right, he's seriously damaged his career.
Nifong does have one thing in his favor in the bar proceeding: that the law and rules of evidence unfairly favor those who accuse others of sexual assault.
I believe Nifong will take the following tack in respect of the withholding evidence charge: that the DNA matches to other men were not materially relevant to the case, and that only the evidence that there were no DNA matches to the lacrosse players was material.
This is an unreasonable position in my opinion, but it is consistent with the prevailing school of thought among legal theorists that evidence of promiscuity on the part of the alleged victim is not a legitimate issue for the defense to raise. Feminists have long complained that male rape defendants had in the past gotten a pass from juries in making reference to a victim's sexual history, and have succeeded in changing the rules of evidence on this point.
It is unreasonable in this case not only because the feminist position goes too far, but in this particular case, the alleged victim had claimed she had not had sex for a week (or two, was it?) prior to the alleged rape, so the evidence of DNA matches with other men impeaches her credibility (Nifong will have to respond that DNA can in theory be found on a person after a longer period of time than that).
So I think Nifong's achievable goal in the bar proceeding is not to demonstrate that he acted reasonably, but rather that he acted in what he saw as good faith.
If he successfully convinces the bar committee that he acted in good faith, even though unreasonably, I can see him getting by with a suspension and not permanent disbarment.
If he is suspended, he may even be able to continue as DA, since he has no boss to fire him. He would have to restrict himself to purely administrative duties and require his staff to handle all cases.
This might conceivably help excuse withholding of evidence, but will it excuse lying to the judge about it?
"I believe Nifong will take the following tack in respect of the withholding evidence charge: that the DNA matches to other men were not materially relevant to the case, and that only the evidence that there were no DNA matches to the lacrosse players was material."
It doesn't matter what he thought or what his reasoning ostensibly was, or what he thought was material. He doesn't get to decide on behalf of the defense what is material or what is admissable on behalf of the court. NC law is clear: all forensic evidence and forensic testing results MUST be turned over to the defense, period, end of story. There are no exceptions for sexual assault or rape cases. Further, the state bar has charged that it was a deliberate effort to conceal the evidence and that he lied on FIVE occasions to the court about it what he knew, when he knew it, and his excuses for failing to follow the law.
In addition to all that, there is an exception in the rape shield law to evidence of sexual activity contemporaneous to the alleged events charged. In this case, the evidence of sexual contact with a a number of men contemporaneous to the alleged event could and would explain the slight vaginal swelling and is certainly relevant and material to the theory the defense has prepared, so the impeachment aspect that you cited wasn't all that was at stake in terms of the undisclosed DNA evidence.
Nobody is going to buy the "good faith" defense. The evidence is to the contrary. Nifong has already tried to explain his behavior and got himself into more trouble with those lies. It's being reported now that he lied to the state bar as well.
He can't continue as DA if he is suspended.