Attorney General Jeff Sessions, after being chided by President Trump for being weak, recently declared a war on leakers and made clear that the news media was also on his mind. “We respect the important role that the press plays and will give them respect, but it is not unlimited,” he said. “They cannot place lives at risk with impunity.” Two days later, Rod J. Rosenstein, the deputy attorney general, tried to clean up the record. “The attorney general has been very clear that we’re after the leakers, not the journalists,” he said.

For all the overblown statements about “lives at risk,” the administration has no poker face. Journalists’ inside sourcing about the wars within the White House walls, the Russia investigations and a shifting foreign policy has been the real driver of the anti-leak fervor.

It seems all but certain that the Justice Department will try to chip away at the subpoena guidelines. Disputes over administrative regulations are rarely the stuff of high political drama. But this is one of those times when the public should be paying attention.

The guidelines run for several pages, but at base they say that prosecutors are to seek testimony and evidence from journalists only as a last resort, and that news organizations should have a chance to go to court to challenge any subpoenas.

The guidelines are far from ironclad. If a prosecutor were to ignore them, a journalist would have no right to go into court and demand they be followed. But they are important. They are rooted in the country’s commitment to press freedom. And over the last four decades, they have, by and large, worked, allowing prosecutors to do their jobs while protecting journalists from routinely being dragged into criminal proceedings.