Partly this is because of widespread misconceptions. The public and the police vastly overestimate the incidence of false reports: The most solid, case-by-case examinations say that only 5 to 7 percent of sexual assault reports are false. Responses to trauma that are often viewed as evidence of unreliability, such as paralysis or an inability to recall timelines, have been shown by neurobiological research to be not only legitimate, but common. And when it comes to the most serious assaults, like rape, people imagine that they are committed by strangers who attack in a dark alley, and base their view of how victims should react on that idea — even though the vast majority of assaults occur between people who know one another.

Many of the same credibility issues surround reports of sexual harassment involving advances made by a boss or someone in a position of power over the victim.

Of course, not every allegation is true. The credibility of those who report sexual misconduct, experts say, should be evaluated by looking for corroborating evidence or using relevant parts of accusers’ backgrounds, like whether they have habitually misrepresented the truth in the past.

But experts say that because many people are not psychologically prepared to accept how prevalent harassment and assault are, they tend to look for reasons to disbelieve. For example, offenders are more likely to choose victims who have been previously assaulted, statistics show, but a woman who reports more than one assault is less likely to be believed.

Here is a look at some of the misconceptions that come up again and again when assessing whether a victim’s account is true.