My antennae tingled during his opening statement when the director claimed that even the Congress that enacted the 1917 Espionage Act feared the relevant provision might violate “American tradition.”

Jim Comey is a really good lawyer. When good lawyers are confident that a law is invalid, they tell you it is unconstitutional. When a legal technician says “unconstitutional,” that’s a hard conclusion he backs with solid argument. On the other hand, when he says “tradition,” he’s in the touch-feely penumbra realm — “y’know, this kinda sorta just doesn’t seem right . . . ”

The director’s problem was soon apparent: “American tradition” was not going to cut it. Unless there is a clear constitutional flaw, the Justice Department is in the (well-supported) habit of telling courts that they are required to presume the constitutionality of congressional statutes. Congress expected nothing less from an FBI director who, in effect, was exercising prosecutorial discretion in nixing an indictment of the very guilty-looking Mrs. Clinton. Comey was going to have to explain why the statute was lacking.

He couldn’t. Again, that should have been no surprise because — if he had a convincing theory, he would have come out of the box with it. There have been cases brought under this law — most of them in the military system, but those are United States courts, too. The law has never been held unconstitutional. Federal prosecutors, moreover, occasionally use the law in plea negotiations — a no-no if government lawyers think a law is invalid. Comey said some lawmakers were nervous about the statute when it was passed — but they still passed it.

In the end, the best the director could do was contend that Justice Department lawyers worried about it. When pointedly asked how he would amend the statute to shore it up, Comey declined to offer a suggestion other than that the committee should contact DOJ.