In computer science the term garbage in, garbage out is used frequently to note that if you have garbage data as an input you will get garbage data as an output. This is applicable in any research. A new study has been released that claims there is no racial bias in polices’ use of lethal force in the United States. Quite a few people have jumped on this because it supports their bias that there isn’t a problem with policing in this country. However, Radley Balko points out a serious flaw in the study. It uses reports written by police officers:
For the purpose of the discussion, let’s break shootings and killings by police into three categories: incidents that were illegal and unnecessary, incidents that were legal and necessary, and incidents that were legal but unnecessary. If you’re asking whether current laws and policies allow for too many police shootings, looking at how many shootings are justified under current law and policy is just question begging. It’s that last category — legal but unnecessary — that we want to explore. Unfortunately, it’s also a category that is plagued by subjectivity and the simple fact noted above: Most of the data we have comes from police reports themselves.
If we were to compile statistics on, say, medical mistakes in an effort to make policies that would improve the state of medicine, we wouldn’t get all of our data from written statements by the accused doctors or hospitals. If we wanted to compile data on conflicts of interest in politics, we wouldn’t rely on members of politicians to self-report and adjudicate when their vote may have been influenced by a campaign donation. But this is essentially what we do with shootings by police officers.
The study is simply an extension of the phrase, we investigated ourselves and found that we did nothing wrong. Studying police use of force in the United States is difficult because most of the data is created by the police themselves. There is very little third-party oversight and what little exists is usually tied to the law enforcement community in some manner.
I’m sure Jeronimo Yanez, the officer who killed Philandro Castile, wrote a report that exonerated him of wrongdoing. This isn’t just because he wants to avoid punishment but also because he probably wants to justify his actions to himself. We humans are great at twisting logic to justify our actions to ourselves. Thieves will tell themselves that since the person they were stealing from was wealthy no real harm occurred to him and therefore the theft was justified. Domestic abusers will tell themselves that they have to hit their partner in order to teach them important lessons. Police, likewise, will tell themselves that lethal force was necessary to preserve their lives. We cannot rely on the reports thieves, domestic abusers, and police write about their own actions because they are necessarily biased. So long as rely on such data as our input we’re going to get garbage as our output.