People killed by police in the UK (pop: 64m) since January 2010: 3
People killed by police in Canada (pop: 35m) since January 2010: 20
People killed by police in Australia (pop: 23m) since January 2010: about 20 (my estimate using numbers from here)
People killed by police in the US (pop: 318m) since January 2013 (I got tired and gave up counting): 419