The Bill of Rights is and should be popular. It is something most Americans overwhelmingly support. Conservatives love the Second Amendment and honest progressives defend the First Amendment. But it is sometimes harder for the public to embrace and champion the due process of the Fourth, Fifth, and Sixth amendments.

Why? Because to defend due process sometimes means defending trials, lawyers, and privacy for people accused of heinous crimes. Understandably, some don’t choose to think about the fact that the worst imaginable people in our society are still guaranteed rights as citizens—the right to trial by jury, the right to an attorney, the right to be free from suspicionless searches.

Who would want to defend the rights of awful rapists and murderers? The easy response is that we defend due process to try to ensure that the person who is punished is guilty of the crime. There have been times in our country’s history when due process was ignored or absent. The lynching of black men in the South is the most egregious. The internment of Japanese Americans during World War II is another stain on our history when we strayed from due process.

Last year, President Obama signed into law a bill that allows for the indefinite detention without charge of an American citizen. When I asked a fellow Senator if this meant that an American citizen could be sent to Guantanamo Bay without charge or jury trial, and be indefinitely detained for the rest of their life, he responded: “If they are dangerous.”

But this only begs the question: Who gets to decide if they are dangerous?

We have a Bill if Rights to protect us—innocent, law-abiding Americans citizens, not criminals, not terrorists, not enemies.

The Bill of Rights exists to protect citizens like Richard Jewell, the security guard whose efforts helped save lives during the bombing of the 1996 Olympics in Atlanta. After the bombing, Jewell became a suspect in the investigation and was quickly convicted in the court of public opinion. Everyone rushed to label him a terrorist.

After 88 days of media speculation and slander, Jewell was formally cleared of all charges. They eventually caught the real culprit who set the bombs. Today, one could easily imagine some calling for Jewell’s constitutional rights to be waived and for him to be indefinitely detained as an enemy combatant.

But luckily for Jewell, and all Americans, we have a Bill of Rights that protects us.

If Jewell had been a black man in Jim Crow South he might have been lynched from the nearest tree. Due process not only protects the innocent, but becomes a necessity if democratic majorities begin to oppress minorities, which, tragically, has happened in our history.

Last week the Supreme Court decided that DNA evidence can be extracted from arrestees—someone merely accused of a crime. In the past, DNA has been extracted from individuals convicted of a crime, with it being understood by all that one’s liberties and access to normal freedoms is curtailed after conviction.

The problem with allowing DNA to be forcefully taken from accused individuals is that people wrongly accused could be made part of a national registry. Some would respond that if you’ve done nothing wrong, you have nothing to fear from a national registry. That might be true if government were always and everywhere comprised of angels. Experience tells us that government officials often fall short of being angelic.

Think of the recent IRS targeting of the President’s political opponents.

On the other side, some would argue that the DNA evidence obtained helped us catch a rapist. This is true but, interestingly enough, in this case, the DNA evidence could have been collected after his conviction for the crime for which he was arrested.

In his dissent in Maryland v. King, Justice Scalia makes this point well, “the ironic result is … that the only arrestees to whom the outcome here will ever make a difference are those who have been acquitted of the crime of arrest.”

So, really by limiting DNA collection to only convicted criminals all we are really doing is excluding people from the invasive search of DNA who are deemed innocent. Scalia dissented because he believes that DNA should not be collected from those merely accused. I agree.

Scalia said, pithily, in his dissent: “I doubt that the proud men who wrote the charter of our liberties would have been so eager to open their mouths for royal inspection.”

The Founding Fathers knew that the protection of liberty was contingent upon never giving government too much power or trust. Maryland v. King gives government a benefit of the doubt that common sense, history and the Constitution tell us it does not deserve.

Rand Paul is a Republican senator from Kentucky.