In the eight months since the killing of unarmed teenager Michael Brown brought increased focus on police violence, more and more officer-involved shootings that also involve mental illness have come to light.
Mexico has called on the US Justice Department to monitor investigations into three US police shootings of Mexican nationals within the past month, arguing that the incidents "cannot be seen in an isolated manner".
The charity Crimestoppers is offering up to £5,000 reward for information leading to the arrest and conviction of those responsible for the shootings.
Between 2007 and 2013, there were 364 officer-involved shootings in the Philadelphia police department, the report found.
Zaid al-Hilli said police were called following a row with his younger brother Saad, nearly a year before the fatal shootings in September 2012.
More recently, France was convulsed by a series of murders over nine days last March including three French soldiers of north African descent killed in two separate shootings, and a rabbi, his two young sons and a third child in an attack on a Jewish school in Toulouse.
Two fatal police shootings unfolded within 14 hours, both in lakeside towns in the same corner of north-west Idaho.
"And so when you ask somebody: 'Oh, I need 14 years of data from you,' and they keep half their data in files in a room somewhere in boxes, and the other half is on a computer that doesn't associate, say, officer-involved shootings with vehicular homicides, or Tasers – you're asking them a lot".
To gain insight into the use of lethal force by police, Klinger said, the public also needs data on violent encounters that turned out not to be fatal – because most police shootings aren't.
John Lee, 29, was arrested following a high-speed chase in nearby Washington state after the shootings, which occurred on Saturday.
Ballistics tests were expected to help determine which weapons might have been used in the shootings.
