For much of 2015, Fox News and the New York Post decried a "war on cops," specifically blaming the Black Lives Matter movement — and its criticisms of excessive use of force by cops — for enabling a wave of violence against police officers in the US.

Yet with the year over, it looks like 2015 was one of the safest years to be a police officer in America. Since 1960, only 2013 had fewer on-duty police officer deaths than 2015.

The Officer Down Memorial Page, which tracks police officer deaths, estimated 129 police officers died in the line of duty in 2015, down 3 percent from 2014. This continued the long-term trend downward, based on the organization's statistics going back decades.

The single biggest cause of death in 2015 was gunfire. Out of 129 deaths, 39 were gun homicides and two were accidental shootings. But deadly shootings were down from 2014, when 49 cops died to gunfire.

The overall drop in on-duty police deaths coincides with a dramatic drop in crime in recent decades: Violent crime rates in the US dropped by roughly 49 percent between 1994 and 2014, according to FBI data.

Still, police organizations claim officers feel increasingly threatened following the growing criticisms and protests against law enforcement over racial disparities in use of force, particularly after the police killings of Eric Garner in New York City, Freddie Gray in Baltimore, and Michael Brown in Ferguson, Missouri. Tensions in police departments were especially high after the December 2014 killings of New York City police officers Wenjian Liu and Rafael Ramos and the April 2015 riots in Baltimore over Gray's death while in police custody.

In response, police in 2015 sometimes leveled their own criticisms and protests. In comments to media, Chuck Canterbury, national president of the Fraternal Order of Police, the country's largest police union, suggested cops should be shielded from attacks in hate crime legislation. Reacting to public scrutiny over high-profile cases of excessive force, New York City and Baltimore police officers appeared to engage in a "slowdown" in which they carried out fewer arrests — a tactic that police have historically used to protect themselves, avoid public scrutiny, purposely decrease public revenue raised through citations, and show critics what life might be like without law enforcement.

Some defenders of police referenced the "Ferguson effect": the idea that more scrutiny of police since the Ferguson, Missouri, protests has demoralized cops and emboldened criminals, leading to more crime. A report by the Brennan Center for Justice, a criminal justice group, found that murder rates significantly increased in some cities in 2015, but overall crime dropped.

The protests by police also sometimes backfired, leading to further criticisms that law enforcement are too sensitive and trying to escape public accountability. In a January 2015 Quinnipiac University survey, 57 percent of nearly 1,200 respondents in New York City said cops should be disciplined if they deliberately made fewer arrests or wrote fewer tickets.

But many defenders of police continue claiming that cops are under a serious threat — potentially in an attempt to shift the conversation from what cops are doing wrong.

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