The editor in chief of Time Inc. on Saturday defended his decision to surrender a reporter's notes to a federal prosecutor investigating the unmasking of a CIA agent.

Norm Pearlstine (search) has been heavily criticized since announcing July 1 that Time magazine would turn over staff writer Matt Cooper's (search)'s notes, e-mails and related documents to a grand jury investigating how reporters learned the agent's name.

"I would not do anything different in terms of the decision," Pearlstine said Saturday at a writers conference in Texas.

Pearlstine's decision broke ranks with The New York Times, which allowed a reporter to be jailed for refusing to cooperate with the investigation.

Pearlstine said withholding Cooper's notes was putting other Time staffers at risk of being subpoenaed by prosecutor Patrick Fitzgerald (search).

"I did not think it was appropriate to subject the institution to this kind of regulatory scrutiny," he said.

He said use of confidential sources often becomes "a question of where to draw the line. I probably chose to draw it at a place where other editors might not have drawn it."

Since turning over the documents, Cooper has said that Karl Rove (search), President Bush's deputy chief of staff, told him about the agent in a 2003 phone call.

The New York Observer in an editorial said that Pearlstine "rolled over" for Fitzgerald. The New York Times has questioned whether a high-ranking source would ever risk being named by speaking to a Time magazine reporter.

Pearlstine said he expected criticism from others in journalism.

"I knew this was a big deal," he said. "I think it's an important debate."

Pearlstine said Time magazine continues to use confidential sources in high-profile stories, citing as examples reports on Guantanamo Bay, security at nuclear power plants and suicide bombings in Iraq.

He acknowledged that cases such as the one that ensnared Cooper could hinder journalists' ability to cultivate highly placed sources.

"Prosecutors, and plaintiff's attorneys as well, are much more aggressive in court seeking disclosure of confidential sources, which could have a chilling effect," he said.

Legislation has been introduced in Congress to protect reporters from having to identify their confidential sources. So-called shield laws already exist in 31 states and the District of Columbia.