In his Commentaries on the Laws of England, William Blackstone declared, "It is better that ten guilty persons escape, than that one innocent suffer." In an 1785 letter, Benjamin Franklin was even more exacting: "That it is better 100 guilty Persons should escape, than that one innocent Person should suffer, is a Maxim that has been long and generally approv'd, never that I know of controverted."

In 2011, the U.S. Department of Education took a different position.

That was the year the department's Office of Civil Rights sent a "dear colleague" letter reinterpreting Title IX of the Education Amendments Act of 1972. That section reads: "No person in the United States shall, on the basis of sex, be excluded from participation in, be denied the benefits of, or be subjected to discrimination under any education program or activity receiving Federal financial assistance." The OCR's letter declared that sexual assault is "a form of sex discrimination prohibited by Title IX." (Sexual violence is a great deal more than discrimination, of course, but set that aside for the moment.) Afraid of losing their federal funding, colleges then set about devising grievance procedures to address complaints of sexual harassment and sexual assault on their campuses.

The problem: The OCR decreed that these Title IX tribunals must eschew "the 'clear and convincing' standard"—that is, that they cannot refuse to punish people unless "it is highly probable or reasonably certain that the sexual harassment or violence occurred." Such procedures, the office explained, "are inconsistent with the standard of proof established for violations of the civil rights laws." Instead the tribunals should embrace the weaker "preponderance of the evidence" standard, in which "it is more likely than not that sexual harassment or violence occurred."

Without wading into the weeds of specific cases (I refer readers to the excellent and thorough reporting of my Reason colleague Robby Soave), it is apparent that applying a lower standard of proof means that it is easier to punish those guilty of sexual violence. Conversely, it also means that more innocent people will be falsely found guilty of offenses they did not commit.

So how high a risk of false conviction do the innocent face under the OCR's Title IX guidance standards? John Villasenor, a professor of public policy at the University of California, Los Angeles, set out to answer that in a study that uses probability theory to model false Title IX convictions under the preponderance of the evidence standard. What he found should take all fair-minded Americans aback.

Villasenor begins by examining how legal scholars assess the stringency of burden of proof when it comes to determining the guilt or innocence of defendants. For example, surveys of judges, jurors, and college students find that when it comes to determining guilt beyond a reasonable doubt, they converge on a 90 percent probability as the threshold for finding that a defendant has committed the infraction as being fair. For

the preponderance of the evidence standard, the figure is 50 percent. The lower standard of proof doesn't merely make it more likely that someone will be convicted; it provides prosecutors a greater incentive to risk bringing a case.

Villasenor outlines an example in which 100 people are accused of wrongdoing. He supposes that 84 are guilty and 16 are innocent. Now suppose that the tribunal convicts 76 of the guilty while letting eight guilty individuals go, and that it acquits 12 of the innocent while convicting four. The overall probability of conviction is 80 percent (76 guilty + 4 innocent), and by definition the probability of being innocent is 16 percent. But since four innocent defendants are convicted, there is a 25 percent probability (4 out of 16) that an innocent person will be found guilty.

Villasenor aims to be very conservative in his estimations, so he decides to use a four percent threshold that an innocent defendant would be wrongly convicted under the beyond-a-reasonable-doubt standard. (He draws that number from a 2014 study that estimated at least 4 percent of death-sentenced defendants in the U.S. would likely be exonerated.) To be even more cautious, Villasenor does additional probability calculations using a 1 percent threshold that an innocent person would be convicted under the reasonable-doubt standard.

If there is a four percent probability that a tribunal using a reasonable-doubt threshold of 90 percent will return a guilty verdict in a case, what happens when that tribunal shifts to a preponderance-of-the-evidence threshold of 50 percent? "When the preponderance of the evidence standard is used to judge an innocent defendant, a guilty verdict would be returned with probability 33 percent," finds Villasenor. What happens if the reasonable doubt threshold is tightened to an implausibly stringent 1 percent? Even in that case, an innocent person would face "a 19 percent probability of being found guilty under a preponderance of the evidence standard."

Villasenor tests his conclusions using various probability models. Using even the most conservative assumptions, he concludes, "an innocent person facing a 4 percent probability of being found guilty under the beyond a reasonable doubt standard would face a 20 percent probability of being found guilty under a preponderance of the evidence standard."

The OCR's defenders argue that campus tribunals cannot fairly be compared to criminal courts of law. Well, yes: Besides the relaxed burden of proof, they also dispense with many of the basic aspects of due process, such as a right to counsel and a right to question the accuser. Villasenor thus concludes that "innocent defendants in Title IX proceedings may be even more exposed to guilty verdicts than the approach used here suggests."

During her Senate confirmation hearing, Democratic committee members pressed Betsy DeVos to uphold the Obama administration's Title IX guidance if she became secretary of education. She responded that such a pledge was "premature." DeVos added, "If confirmed, I look forward to understanding the past actions and current situation better, and to ensuring that the intent of the law is actually carried out in a way that recognizes both…the rights of the victims, as well as those who are accused."

Sexual assault is wrong and absolutely should be punished. Victims' rights advocates are clearly right when they argue that the lower burden of proof makes it easier to punish the guilty. But at what cost to the innocent?