The news media have been worrying this summer about the Valerie Plame leak investigation, which has landed a New York Times reporter in jail. Meanwhile, a potentially far more dangerous threat to the press has emerged in a federal criminal indictment that lists contacts between reporters and sources as "overt acts" in an alleged conspiracy to commit espionage.

The case involves two former officials of a pro-Israel lobbying group, Steven Rosen and Keith Weissman, and their alleged dissemination of classified information that they received from a former Defense Department analyst named Lawrence Franklin. The Aug. 4 indictment charged that the three disclosed secret information about U.S. policy toward Iran and terrorism to an unnamed foreign power, identified by sources as Israel.

Like the Plame investigation, the indictment is politically sensitive. The American Israel Public Affairs Committee, where the two lobbyists worked, is one of the most potent advocacy groups in Washington. AIPAC, as the group is known, fired Rosen and Weissman in April, and the group has seemed eager to distance itself from the fallout of the case. Given the stakes, it has received surprisingly little attention so far in the media.

But a careful reading of the indictment shows that this is a very peculiar case, indeed, and one that could have damaging consequences -- both for the news media and for lobbying groups that depend on regular exchanges of information with government officials. If the prosecution succeeds, it could change the way business is done in Washington.

The heart of the indictment is a conspiracy count, which alleges that "in an effort to influence persons within and outside the United States government, Rosen and Weissman would cultivate relationships with Franklin and others" and then transmit the classified information they obtained "to persons not entitled to receive it." The indictment lists 57 "overt acts" to further this alleged conspiracy.

What should worry the news media is that five of these alleged overt acts involve contacts by Rosen, Weissman or Franklin with unidentified journalists. (A sixth involves a contact with a senior official of an unidentified think tank.) The indictment doesn't allege that these media contacts were illegal in themselves. That's why conspiracy indictments are such convenient catchalls for prosecutors: They can list "overt acts" that aren't illegal as evidence of a conspiratorial plot -- in this case, allegedly to violate the Espionage Act.

One of the unnamed reporters whose contact with Rosen and Weissman is cited in the indictment is Glenn Kessler, a Post diplomatic correspondent. According to a June 3 Post article, the two AIPAC lobbyists jointly called Kessler in July 2004 and relayed information they had received that day from Franklin about possible Iranian attacks against Israelis who were operating undercover in Iraq. Kessler never published an article about the tip.

It turned out the FBI was monitoring the lobbyists' call with Kessler. At that time, Franklin reportedly was cooperating with the government. The FBI apparently had authorized Franklin to give the AIPAC officials the classified information about Iranian threats in Iraq in an effort to "sting" them -- in the expectation that they would transmit the information to the Israeli Embassy, which they allegedly did.

Ironically, Rosen joked in his conversation with Kessler about "not getting in trouble" for transmitting the information and said, "At least we have no Official Secrets Act," according to a partial transcript of the bugged call that was quoted by the JTA (formerly the Jewish Telegraph Agency).

And that's the essential point: We don't have an Official Secrets Act in America that bars disclosure of information except in specific, limited situations -- and that's for good reason. We know that such laws chill the open flow that is essential for a healthy democracy. Explains Kevin Baine, an attorney at Williams & Connolly who advises The Post on this and other First Amendment cases: "If the disclosure of newsworthy information about the national defense to reporters for the purpose of publication can constitute espionage, that places enormous power in the hands of prosecutors, because information about national defense is passed on every day to reporters in this town."

The allegations against Rosen, Weissman and Franklin are serious. The government is right to protect sensitive intelligence about Iran and terrorism from disclosure to foreign countries, even close allies such as Israel. But the indictment of the AIPAC lobbyists crosses a subtle line. It moves beyond protecting information to chilling any discussion of it outside the government's tight circles. Stifling debate about foreign policy is the last thing America needs right now.