A Fox News Channel reporter will fight any attempt to force her to reveal her sources for a story about Colorado theater shooting suspect James Holmes, the reporter's lawyer said in a letter made public Thursday.

The attorney also accused Holmes' lawyers of misleading the judge in Holmes' case about their attempts to contact Fox News.

Shortly after the July 20 shootings that left 12 dead and 70 injured, New York-based Fox reporter Jana Winter wrote a story that cited unidentified law enforcement sources to describe the contents of a notebook Holmes sent a psychiatrist.

Holmes' lawyers say whoever told Winter about the notebook violated a gag order imposed by Judge William Sylvester, and they want Sylvester to punish the person responsible.

After numerous investigators testified under oath that they did not speak to Winter, Holmes' lawyers said they wanted to subpoena Winter to force her to identify her sources.

Winter's lawyer, Dori Ann Hanswirth, said in a Jan. 29 letter to Holmes' attorneys that shield laws in New York and Colorado protect Winter from demands to reveal her sources.

"We urge the defense to abandon its pursuit of testimony from Ms. Winter," the letter said.

Hanswirth sent a copy of the letter to prosecutors, who submitted it to the judge in a motion.

Predicting the outcome of attempts to learn the identity of unnamed sources is difficult because the facts vary from case to case, said Gregg Leslie, legal defense director of the Reporters Committee for Freedom of the Press.

"This case has been particularly troublesome because there has been a reflexive move to seal everything," Leslie said. "You often see your biggest leaks when there's too much of an attempt to clamp down on things."

Hanswirth's letter accused Holmes' lawyers of falsely claiming they have tried to contact Fox News.

In a motion filed last week, Holmes' lawyers referred to "current attempts to communicate with Fox News." Hanswirth's letter said there had been no such attempt and called the assertion a "misrepresentation" and "highly inappropriate."

Hanswirth demanded an explanation for the assertion.