Reply to post: Re: Studying police officers improves their behaviour

Re: Studying police officers improves their behaviour

"It shows that IF PEOPLE THINK you have a camera, they will behave better."

The "study" does not tell us what people were thinking -- I won't call it an experiment, as it was clearly not even double-blind -- but we do know it involved geographically distinct forces. We also know that apparent placebo effects (and increasingly, nocebo effects) are usually interpreted as bringing into question the experimental hypothesis.

In an experiment where the control shows the same result, that generally suggests any observed change in behaviour cannot be attributed to the controlled variable. Indeed this is the reason for having controls. But in this case it is being reported (with the active encouragement of those involved in the research) as showing that the effect is so powerful that it spreads. If this were an experiment on homeopathic treatment, then this type of sloppy post hoc analysis offered by the researchers would be equivalent to arguing that homeopathic treatment is so powerful it actually cures people in the control group --- perhaps it does, but that would be a very controversial analysis!

There are other aspects of the publicity behind this publication that are concerning, including the conflation of "the number of reports of attacks" with "the number of attacks" (which are *very* different things), and the glossing over of the apparent increase in force used by the police in the camera wearing group, with no analysis of whether this was justified. If this increase in force did not occur in the control group, then that would be the key finding, not the reduction in complaints across experimental and control groups.

As with many things, the impact of body cameras is not at all straightforward.

For another perspective: http://www.slate.com/articles/technology/future_tense/2014/09/ferguson_body_cams_myths_about_police_body_worn_recorders.html