We have a tendency to redefine evidence to meet the needs of our beliefs

 From Prevalence-induced concept change in human judgment by David E. Levari, et al.  From the paper:

Do we think that a problem persists even when it has become less frequent? Levari et al. show experimentally that when the “signal” a person is searching for becomes rare, the person naturally responds by broadening his or her definition of the signal—and therefore continues to find it even when it is not there. From low-level perception of color to higher-level judgments of ethics, there is a robust tendency for perceptual and judgmental standards to “creep” when they ought not to. For example, when blue dots become rare, participants start calling purple dots blue, and when threatening faces become rare, participants start calling neutral faces threatening. This phenomenon has broad implications that may help explain why people whose job is to find and eliminate problems in the world often cannot tell when their work is done.

As with all studies, subject to replication.

However, it is an interesting and, I suspect, prevalent issue.

When violence against women declined based on some successful legal reforms and social changes, we saw an increasing inclination among advocates to redefine sexual violence to include actions not ostensibly or obviously sexual violence.  There for a while we had talking heads claiming that American university campuses were suffering rape rates higher than the worst seen in war zones.  It was all nonsense.  American collegiate women are safer compared to their lower class sisters who do not attend university.  Advocates tend to be upper class and wealthy and solve what they perceive as the highest priority problems for their class with little regard to the well-being of others and actual demonstrable dangers.

It was just one of innumerable linguistic and definitional instances of scope creep.

Likewise, the twenty years after the great civil rights successes of the 1960s, it became in most social circles taboo to use racial or ethnic stereotypes or demonstrate demonstrably racist behaviors.  As visible racism declined, we saw the rise of hoax hate crimes to fill the gap.  Those on the right mocked those of the left and celebrated that we were so short of obvious racism, that we were having to manufacture hoax racist attacks in order to make up the shortfall.

Similarly with crime, though that is perhaps an even more complex topic.  From the high in the mid 1990s, all manner of crime has steadily fallen, especially violent crime.  For reasons that are suspected but not deterministically reliable.  And as our neighborhoods have gotten safer, our definition of dangerous crime has expanded.  In some circles, words are now equated to violence in order to fill the need for the crime that is believed to be there.

This tendency to redefine evidence to meet the needs of beliefs is common.  Interesting to see someone trying to demonstrate and quantify it.

View ORCID ProfiDavid E. Levari, et al.