Martina Orlandi, McGill University

Suppose you’re watching the news, and you learn that someone, let’s call her Mary, has been accused of murdering her colleague Sally. There is compelling evidence that Mary is guilty. Several of Mary’s colleagues come forward to defend her innocence. They insist Mary is a truly kind person. As a proof, they say Mary has never attempted to murder any of them.

Does the fact that Mary has not murdered her colleagues increase or decrease your confidence that Mary has murdered Sally? Probably neither. The fact that Mary has never attempted to murder her colleagues says nothing about whether she murdered Sally. It’s irrelevant.

Similarly, if someone is accused of stealing your watch, the fact that they did not steal the watch of your friend sitting right next to you says nothing relevant about whether they stole yours.

As reasonable as these arguments may sound, their logic is often ignored when it comes to sexual allegations.

The issue of what people take to be good evidence is one that philosophers have debated for centuries. Philosopher David Hume famously said a “wise man … proportions his belief to the evidence.” My research on irrational phenomena has led me to confront the relationship between evidence and biases of all kinds.

Philosopher Gilbert Harman argues in his book Change In View that people often refuse to revise our beliefs even in the face of strong counter-evidence. People rationalize to maintain their false but dear beliefs. Even when they don’t, research has shown that people’s threshold for accepting a belief increases when it comes to dealing with one that’s particularly uncomfortable. Worse, irrational behaviour is not exclusively a prerogative of the uninformed.

Educated people are just as guilty of it, as recent research on anti-vaccination views show: researchers who interviewed more than 5,000 people in 24 countries found that people’s education has no significant relationship with anti-vaccination attiudes. The study also reports that attempts to debunk vaccine-related myths through evidence are ineffective or counterproductive.

The case of sexual allegations is another example of how often debates go off-track and become irrational.

A decent man?

In the wake of Christine Blasey Ford’s accusation of sexual assault towards Brett Kavanaugh, a letter signed by 65 women testified to his moral character and his good behaviour towards them.

More recently, after Lucy Flores and Amy Lappos brought Joe Biden’s inappropriate behaviour into the spotlight, Meghan McCain called Biden “one of the truly decent and compassionate men in all of American politics,” recalling the support she received from him after her father’s diagnosis of brain cancer.

After Leeann Tweeden accused senator Al Franken of sexual misconduct, Jess McIntosh, Franken’s spokesperson, said: “I’ve taken thousands of those photos with him and I’ve never seen any behaviour that was questionable. We were together non-stop — like, the only two people staying in a hotel — and nothing happened. I felt completely comfortable.” Similarly, Karri Turner said “there was nothing inappropriate toward me.”

The implication is that because Kavanaugh, Biden and Franken behaved appropriately with some women, then this tells us something informative about whether the allegations from other women are true.

For their defenders, the implication is that Kavanaugh, Biden and Franken are good guys, and they are good guys precisely because they behaved properly with some women. Because they’re good guys and presumably only non-good guys sexually offend, this should decrease our confidence that they didn’t offend Ford, Flores, Lappos and Tweeden specifically.

A question of character?

Perhaps the reason why people think that these positive testimonies are relevant is that the action of sexual misconduct is linked to the perpetrator’s character. This idea connects with Aristotle’s famous claim that character traits tends to manifest repeatedly.

If we follow this idea, it suggests that sexually harassing someone conveys the message that they are the kind of person who is a sexual harasser.

Because character traits tend to manifest repeatedly, we implicitly think that if someone harassed one person, they are likely to have also harassed others. So if it can be shown that not everyone they interacted with has been sexually harassed by them, then this may decrease confidence in the belief that they have harassed those women at that specific time.

But while it may be true that character traits tend to manifest repeatedly, repeatedly doesn’t mean always.

American journalist Megan Garber has called this situation “the familiarity fallacy.” She explains how easy it is to rationalize abuse when committed by those we know personally. Garber says knowing someone doesn’t constitute a legitimate defense from accusations: “an abuser will not abuse everybody.”

A person may respect one person’s personal boundaries, yet disregard another’s. This may be due to perceived power over the second person due to their personal vulnerability, or their social identity. Sexual harassment is not about sex, but is about asserting dominance. Factors such as a person’s racialized identity, their class, their ability, their age, the amount of power they are perceived to hold in a particular situation may all also render people more vulnerable to being sexually harassed or otherwise having their personal boundaries disrespected.

Read more: I am not your nice 'Mammy': How racist stereotypes still impact women

Predators may take advantage of situations where they think no witnesses, other than the victim, are present.

Good-character testimonies don’t shield someone from the possibility that they have sexually harassed someone else.

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Martina Orlandi, PhD Candidate in Philosophy, McGill University

This article is republished from The Conversation under a Creative Commons license. Read the original article.