The government's fidelity to the Constitution is never more tested than in a time of crisis. The urge to do something—or to appear to be doing something—is nearly irresistible to those whom we have employed to protect our freedom and to keep us safe. Regrettably, with each passing violent crisis—Waco, Oklahoma City, Columbine, 9/11, Newtown and now the Boston Marathon—our personal freedoms continue to slip away, and the government itself remains the chief engine of that slippage.

The American people made a pact with the devil in the weeks and months following 9/11 when they bought the Bush-era argument that by surrendering liberty they could buy safety. But that type of pact has never enhanced either liberty or safety, and its fruits are always bitter.

The Constitution is the supreme law of the land. It was written to create and to restrain the federal government. Every person who works for any government in the U.S. has taken an oath of fidelity to the Constitution, not unlike the presidential oath, which induces a promise to preserve, protect and defend the Constitution.

The chief and final interpreter of the Constitution is the Supreme Court. One may not always agree with its interpretations, but they are, as legal scholars sometimes say, "infallible because they are final." Those interpretations are particularly final when we have relied on them for generations.

One of those rulings underscores the primacy of constitutional protections, no matter the environment in which they are claimed. Indeed, after the Civil War had ended and President Lincoln was dead, the Supreme Court in a case called Ex parte Milligan (1866) rebuked and reversed Lincoln's unilateral assaults on personal freedoms in the North and in so doing reminded us that the Constitution was written for good times and for bad, and its protections cover all persons at all times and under all circumstances who have any contact, voluntary or not, with the government.

The court has also ruled consistently throughout the 20th century that just as the First Amendment protects the freedom of speech, it also protects the freedom not to engage in speech. One hundred years after Milligan, the Supreme Court first recognized and articulated the constitutional basis for the right to remain silent in the Miranda case. That right is a natural right that is inherent in all human beings, and it is arguably articulated in the First and Fifth Amendments.

But since the court understood that most folks don't know that they have the right to remain silent in the face of government demands for speech, it mandated that all governments—local, state and federal—comply with their affirmative obligation to tell everyone in their custody whom their agents wish to interrogate about the existence of this right, as well as the obligation of the government to honor it faithfully once it has been invoked. That has consistently been the law of the land for the past 50 years.

The pact with the devil occurred in the fall of 2001, when then President George W. Bush and Congress decided that they would use the machinery of the federal government to secure safety, rather than liberty. So, the Bush-inspired Patriot Act permits federal agents to write their own search warrants, and the Bush-inspired new FISA statutes permit search warrants of some Americans' phone calls without a showing of probable cause as the Constitution requires, and the Bush-era intimidation of telephone service providers permitted our overseas spies to snoop on our domestic phone calls. None of this has enhanced safety, and all of it has diminished liberty.

In the Obama administration, the devil has demanded more. In the past five years, we have seen federal spies capturing the keystrokes on our computers, local police using federal dollars to install cameras and microphones on nearly every street corner, and, the latest lamentable phenomenon, the use of false emergencies to undermine freedom.

This began at the Mexican border, where immigration agents have been told to interrogate first and Mirandize later. It moved to Washington, where we have an attorney general who has told federal agents that the extremely limited public safety exception to the Miranda rule can exist for up to 48 hours. And it proceeded to the spectacle of well-meaning FBI agents being told to reject their training and the common understanding of well-regarded constitutional law and interrogate a half-drugged suspect with a hole in his throat whom they were about to charge with mass murder, in utter defiance of Miranda.

The public safety exception to Miranda goes to the safety of the officers and others present at the moment of arrest. It permits the police to express an excited utterance ("Where's the gun?") in an effort to protect themselves before securing the defendant and before advising him of his rights. According to the Supreme Court, it can last for just a few seconds.

The Obama administration's radical reinterpretation of the natural and constitutional right to remain silent is unprecedented, terrifying and disingenuous. Think about this: The governor of Massachusetts, the superintendent of the Massachusetts State Police, the mayor of Boston, the Boston police commissioner, and the head of the Boston FBI office all proclaimed on Saturday morning that the danger had passed and Boston and its suburbs could return to normal. Yet the attorney general in Washington told his FBI agents in Boston to disregard those officials and instead pretend that the public safety was still jeopardized and then expand a 10-second window to 72 hours.

The Constitution was written to preserve freedom by restraining the government. The courts from time to time have required the government to respect the natural law, as well. But when the attorney general arbitrarily changes the law to suit the demands of the people when they are weeping, it fundamentally undermines our freedoms. And a pact with the devil is the most dangerous of all, because his appetite can never be sated.