Correction: An earlier version of this column referred to Chechnya as a country. It is a Russian republic. This version has been corrected.

Attorney General Eric Holder is defending the decision to read Dzhokhar Tsarnaev, the surviving Boston Marathon bombing suspect, his Miranda warning, telling CNN that cutting off his questioning “was totally consistent with the laws that we have.”

That may be true. But three years ago, Holder admitted that “the laws we have” are insufficient for questioning suspected terrorists, and he promised to a major push to change them.

In May 2010, the Obama administration was under fire after delivering Miranda warnings to both the underwear bomber and the Times Square bomber. Initially, Holder defended the decision to Mirandize these suspects after 50 minutes and three hours respectively. But then, suddenly, the attorney general reversed course. In a series of coordinated Sunday show interviews, Holder announced a change in policy: The Obama administration would work with Congress to change the Miranda law to give interrogators greater flexibility in questioning suspected terrorists.

On ABC’s “This Week” Holder declared, “I think we have to give serious consideration to at least modifying that public safety exception,” which gives interrogators time to question suspects without a Miranda warning. “And that’s one of the things that I think we’re going to be reaching out to Congress to do, to come up with a proposal that is both constitutional, but that is also relevant to our time and the threat that we now face.”

On NBC’s “Meet the Press,” Holder called his proposed Miranda changes a “new priority” and “big news,” declaring, “We’re now dealing with international terrorists, and I think that we have to think about perhaps modifying the rules that interrogators have and somehow coming up with something that is flexible and is more consistent with the threat that we now face.”

So what happened?

Apparently nothing. Congress held some hearings. The effort sputtered. Despite the fact that the Democrats then controlled the White House and both houses of Congress, the Obama administration failed to make Miranda reform the “new priority” Holder promised it would be. The “big news” became old news. And now here we are, three years later, and once again we’ve got a suspected terrorist in custody whose interrogation has been stopped by a premature Miranda warning.

In October 2010, the FBI issued revised guidelines on how the “public safety exception” to Miranda could be applied, but those guidelines did not change current law, which Holder said was insufficient for dealing with the threat.

Why are we still operating under the same flawed legal framework for questioning of suspected terrorists that Holder pledged to fix three years ago? Why didn’t the Obama administration follow through on Holder’s promise to work with Congress to change the law? Why are we once again reading a suspected terrorist his Miranda rights before intelligence officials are done questioning him for national security purposes?

Some congressional Republicans are calling for Dzhokhar Tsarsaev to be questioned as an enemy combatant. Speaking on the Senate floor, Sen. Lindsey Graham (R-S.C.) suggested that “the surviving suspect — due to the ties that these two have to radical Islamic thought and the ties to Chechnya, one of most radical regions in the world — that the president declare preliminarily that the evidence suggests that this man should be treated as an enemy combatant.”

Unfortunately, ties to “radical Islamic thought” and “ties to Chechnya” are not enough. Hard evidence linked the man who tried to bring down a Northwest Airlines flight over Detroit by carrying a bomb in his underwear to a foreign power engaged in an armed conflict with the United States, but we do not yet have such evidence on Tsarnaev. Tsarnaev and his brother may well have been working for al-Qaeda or one of its affiliates, but without proof it would be very difficult to justify holding him as an enemy combatant.

Cases like this are precisely why we need Miranda reform. If Holder is insistent that we use the criminal justice system to deal with terrorists captured here in the United States, then it is his responsibility to fix the flaws in that system. He promised to do so, and he failed to deliver. Now, because of that failure, another suspect has stopped talking.

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