Whether by design or incompetence, I can't say. But I can imagine why some people don't want us to get an accurate idea of just how common an event this really is:

An average of 545 people killed by local and state law enforcement officers in the US went uncounted in the country’s most authoritative crime statistics every year for almost a decade, according to a report released on Tuesday.

The first-ever attempt by US record-keepers to estimate the number of uncounted “law enforcement homicides” exposed previous official tallies as capturing less than half of the real picture. The new estimate – an average of 928 people killed by police annually over eight recent years, compared to 383 in published FBI data – amounted to a more glaring admission than ever before of the government’s failure to track how many people police kill.

The revelation called into particular question the FBI practice of publishingannual totals of “justifiable homicides by law enforcement” – tallies that arewidely cited in the media and elsewhere as the most accurate official count of police homicides.

The new estimates added crucial framing to a criminal justice crisis in the US that was coming into sharp focus this week. A Justice Department report expected to be published on Wednesday exposed serial civil rights abuses by police in Ferguson, Missouri. On Monday, the president’s taskforce on policing issued recommendations for better data collection as part of a call for top-to-bottom criminal justice reform.