“Due process” is a battle cry throughout the news and across campuses. Conservatives demand due process for those accused; the left insists upon it for accusers. The term is not a weaponized talking point, however; it is a principle of justice.

What is due process? Why it is essential to justice?

In common parlance, due process is the fair treatment that every individual deserves from law enforcement and the judiciary. Accusers should be heard without bias; defendants should be judged on the evidence and through unbiased procedures. In America, the legal meaning of “due process” derives from the common law tradition, the Bill of Rights, laws and court precedents. The protections include “innocent until proven guilty,” the right of cross-examination, legal representation and transparent proceedings.

Because the protections apply to defendants, however, due process is often said to obstruct justice for accusers. Thus, the pendulum swings far in the direction of protecting an accuser. Campus hearings are an example. They stress the need to believe an allegation, which is captured by the phrase “believe the woman” because women reputedly do not lie about sexual assault. Campus hearings invert due process protections. The defendant is guilty until proven innocent; he is denied legal representation and the right of cross-examination; standard rules of evidence are abandoned.

But automatically believing an accuser devolves to abandoning the judicial process altogether. If an accusation is automatically true, then there is no need for investigations or courts to uncover the facts. #MeToo-style public “prosecutions” are a large step in that direction; accusations are tried in the court of human opinion, where they are immediately believed. The accused people are guilty before a trial or any other unbiased investigation.

“Believe the accuser” runs up against human nature. People are not only fallible, but they also capable of bad behavior, such as lying.

Due process acknowledges that accusers can be mistaken, confused, or lying. It attempts to separate evidence from error and malice in order to judge an accused on the former. This is especially important for cases in which a guilty judgment can ruin a person’s life. Third parties — judges, juries, the public — simply cannot know the truth without facts that are evaluated by reasonable standards, such as placing the burden of proof on the person making an accusation.

The dynamic is not an indictment of an accuser who may be honestly wrong about an identification or other key evidence. It happens with some frequency. The mission of the Innocence Project is “to free the staggering number of innocent people who remain incarcerated,” mostly due to errors.

The organization has freed “more than 350 wrongfully convicted people based on DNA.” Confusion is also a large factor, especially in cases involving drugs or alcohol. Differing interpretations can lead to plausible “she said/he said” scenarios through which objective third parties need to sort.

Some allegations are also lies, of course. In a recent Connecticut case, Nikki Yovino was sentenced for falsely accusing two student football players of rape. One of the accused stated, “I lost my scholarship, my dream of continuing to play football and now I am in debt $30,000.”

Western jurisprudence, especially due process, is organized around the reality that people can be mistaken or lie. That’s why a defendant is presumed innocent until proven guilty, with the burden of proof falling to the accuser. The right to face an accuser means an accuser must stare a defendant in the eye, which removes the anonymity through which lies flourish.

The necessity of due process is often contested on the grounds that false allegations are rare. What is the rate? No one knows for sure, but early FBI sources place the rate of false accusations at about 8 percent. Even if it is far lower, however, every defendant deserves a fair trial. Statistics do not alter the fundamentals of justice.

It must be noted: Accusations in the news or on campus are not criminal cases in which due process is mandated. That is true. But traditional due process applies to criminal rather than civil cases or procedures for a reason: criminal procedures have a huge potential to destroy people’s lives in a manner that cannot be remedied. The same is true of cases in the court of public opinion or other unofficial hearings. The “guilty” can lose the accomplishments of a lifetime, with no chance for redemption. “Guilty” students can lose their futures; they are expelled and their records tagged in a way that prevents them from enrolling elsewhere, receiving licenses, or pursuing many desirable professions.

Accusers must be heard. But they should embrace due process and invite a clear spotlight to be shone on every claim they make. The worst barrier to belief for an accuser are false charges brought by others in the past; the public remembers. By contrast, every time an accusation is treated seriously enough to be objectively assessed, the path of the next accuser — female or male — becomes easier.

Wendy McElroy is a research fellow at the Independent Institute and the author or editor of nine books on women’s issues, government and liberty.