"No one knows how many Americans the police kill each year" but since 2008 around 400 "justifiable homicides" occur each year according to FBI statistics.
Here is a breakdown from a 2011 blog post similar (but more extensive) than I am trying to do here.
Thanks to @blacktalkradio for this list of people killed by cops from Jauary 1st 2009 to July 28, 2014
@zkstv @carwinb @biasedreporter Joseph Kerr compiled this list of the estimated dead killed by police since 2009 http://t.co/KEqMZzDsGf
— Black Talk Radio (@blacktalkradio) August 22, 2014
2,235 killed in 5 years is more than the 2,329 that were killed fighting the Taliban and Al Qaeda in our longest war in Afghanistan.
I wanted to examine the numbers state by state.
It is important to realize a few things while looking at this list. It is only a partial list, and it is only a list of those killed by police, and does not include any injuries by gun or other weapon. I am also assuming that Border Patrol numbers are not included as "police" in this list. It was also mentioned that the list does not include anyone killed in prisons, again not mentioning injuries in prison either.
Here is my count of police shootings by state since 2009
Arizona 69 (I am assuming that this list does not include Customs and Border Patrol for border states)
Jim Fisher found California to be the deadliest state in his 2011 survey as well KQED
California was the most deadly state in his findings, with 102 fatal police shootings. California cities took seven out of 17 places in Fisher’s list of cities with the highest number of officer-involved shootings per capita. And almost every case was closed without charges by police internal investigations and district attorney reviews. (emphasis mine)
New Hampshire 6
New Jersey 51
New Mexico 43
New York 163
North Carolina 53
North Dakota 1
Rhode Island 1
South Carolina 27
South Dakota 2
Washington (includes State and DC) 142
Washington DC 13
West Virginia 10