We have been told that the payment to CMU was at least $1 million.
There is no indication yet that they had a warrant or any institutional oversight by Carnegie Mellon's Institutional Review Board. We think it's unlikely they could have gotten a valid warrant for CMU's attack as conducted, since it was not narrowly tailored to target criminals or criminal activity, but instead appears to have indiscriminately targeted many users at once.
Such action is a violation of our trust and basic guidelines for ethical research. We strongly support independent research on our software and network, but this attack crosses the crucial line between research and endangering innocent users.
This attack also sets a troubling precedent: Civil liberties are under attack if law enforcement believes it can circumvent the rules of evidence by outsourcing police work to universities. If academia uses "research" as a stalking horse for privacy invasion, the entire enterprise of security research will fall into disrepute. Legitimate privacy researchers study many online systems, including social networks — If this kind of FBI attack by university proxy is accepted, no one will have meaningful 4th Amendment protections online and everyone is at risk.