The problem remains that the systemic shooting of civilians is a direct result of policies by law enforcement that inappropriately assumes every call-out is the worst-case-scenario and really provide no practical accountability of the officers for using intelligence in place of fear. 
This NPR article uses police data to report that officer shooting deaths numbered 64 in 2016 in the U.S.  Just under 1/3 were actual ambushes in which the officer was killed in a targeted act of murder.  
https://www.npr.org/sections/thetwo-way/2016/12/30/507536360/number-of-police-officers-killed-by-firearms-rose-in-2016-study-finds
However, NPR points out that there is not a reliable statistic for the number of persons shot and killed by police annually.  That is a very telling fact in and of itself.  We have politicians and activists all over it, but an obvious refusal by the federal government to even track the problem to understand its dimensions.  According to the article, The Washington Post attempts to keep tally, and its count was 955.  To be sure, most were criminals in the act of some deadly crime, but without data, how many?
And to put things in perspective by proportion, in 2016 there were 421,459. That means 0.0152% of officers in uniform were killed by gunfire on the job.  That's less than 1%, less than 1/10th of one percent, less than 2/100ths of one percent. 
The Census Bureau estimated U.S. population at 322,762,018 in 2016, making 955 fatal shootings by police occur at 0.0003% in the total population.  
So, obviously the deaths of officers occurs at a much higher rate than the deaths of citizens per capita, but that is without consideration of how many deaths in proportion to how many encounters, etc. 
Meaningful data should not depend upon law enforcement to report nor opponents of law enforcement.  There should be third party data available for analysis, but there seems to be a deliberate purpose in refusing to keep and publish such data by the government. 
And, for comparison, the numbers of deaths of officers by shooting is way down from the 70's and 80's, perhaps as a result of the adoption of paramilitary mentality and training in response to those high deaths.  Conjecture.