New York Times reporter Judith Miller went to jail this week rather than reveal a news source while Matthew Cooper of Time magazine escaped imprisonment after he agreed to testify. The case is far from simple.

Communications lawyers, news organizations and even reporters disagree on whether a confidentiality right does or should exist. Many states have guaranteed this right by enacting “shield” laws. Maine has no such law, and neither does the federal government, although Maine’s William S. Cohen, when he was a Republican congressman, proposed a national reporter’s shield law.

On its face, the issue may seem clear cut: Why should a news reporter be permitted to disobey a prosecutor’s or grand jury’s request any more than any other citizen? The editor in chief of Time, Norman Pearlstine, concluded that “once the Supreme Court has spoken in a case involving national security and a grand jury, we are not above the law …” The Times’ publisher, Arthur Sulzberger Jr., said he was “deeply disappointed by Time Inc.’s decision to deliver the subpoenaed records” and said the newspaper was supporting its reporter.

Mr. Pearlstine was wrong on at least one point. The Supreme Court did not rule on the matter. It simply refused to take the case and let an appellate court ruling stand. Earlier, the highest court has said that such issues should be decided on a case-by-case basis.

So the facts of the present case are important. It arose out of an article by the syndicated columnist Robert Novak disclosing the identity of an undercover CIA agent, Valerie Plame Wilson. Mr. Novak wrote that “two senior administration officials” had told him that Ms. Wilson was “an agency operative on weapons of mass destruction.” Other reporters, including Ms. Miller, got the same information. Mr. Cooper wrote about it. Ms. Miller did not.

The case concerned a federal law making it a felony for a federal official to disclose the identity of a covert CIA agent. But the law says the disclosure must be part of an effort to harm the national security, and it specifically exempts news reporters who may receive the information. A special prosecutor used a grand jury to subpoena reporters’ notes to try to learn whether any officials had leaked the information. A federal judge ordered Mr. Cooper and Ms. Miller to disclose their sources.

So a real question arises whether any crime was committed by anyone. Congress should deal with the matter and open a thorough debate as to whether reporters should get the same confidentiality guarantee already held by lawyers and clients, doctors and patients and priests and penitents. A good case for it can be made.