The Virginia Supreme Court says the state's attorney general does not have the authority to subpoena emails from a global warming researcher.
The court ruled Friday that Attorney General Kenneth Cuccinelli, a climate change skeptic, can't have the emails. Cuccinelli is investigating whether researcher Michael Mann defrauded taxpayers by using manipulated data to obtain government grants.
Mann used to work at the University of Virginia and now works at Penn State. He has been a target of global warming skeptics for his work that shows the world's temperatures have risen since the early 1900s.
Other investigations, including one by the National Science Foundation, have found no wrongdoing by Mann.
Cuccinelli is a Republican who also has waged a high-profile battle against the Obama administration's health care overhaul.