US police forces rethinking tactics

After last week's killing of five officers in Dallas, the deadliest assault on U.S. law enforcement since the Sept. 11, 2001, attacks, nearly half of America's 30 biggest cities have issued directives to pair up police officers on calls to boost safety, according to a Reuters survey of police departments.

And one, Indianapolis, said it would consider the use of robots to deliberately deliver lethal force, an unprecedented tactic until Thursday when the Dallas police department used a military-grade robot to deliver and detonate explosives where the shooter was holed up.

While a wave of anti-police protests since the 2014 killing of an unarmed black teen in Ferguson, Missouri, has revived memories of 1960s protests over civil rights and the Vietnam War, Thursday's shooting marked something different: a willingness to take up arms against police.

Ambushes against police on Thursday and Friday in Tennessee, Georgia and Missouri added to a sense of being under siege and vulnerable at a time when many departments already were grappling with heightened community suspicion over the use of deadly force.

Responding to the Dallas shooting, Denver's police union wants officers to wear riot gear for local protests and to be armed with AR-15 assault rifles while patrolling Denver International Airport, the union said in a letter to the mayor published in The Denver Post.

The most immediate change is the pairing up of officers. Thirteen of the country's 30 biggest city police department said they are pairing up officers - a change that could strain already thinly staffed police ranks in some regions.

(The 13 are New York City, Chicago, Houston, Philadelphia, Phoenix, San Diego, San Jose, San Francisco, Indianapolis, Seattle, Memphis, Boston and Portland.)

In Albuquerque, New Mexico - one of several cities dealing with an officer shortage - pairing officers could mean "possibly longer response times for lower priority calls," said its police spokesman, Simon Drobik. And for cities with tight municipal budgets, some question whether this expensive strategy can last beyond the short term.

Doubling up officers "is a resource-intense approach and it will be a significant challenge for some police departments to sustain that strategy for very long," said Thomas Manger, president of the Major Cities Chiefs Association (MCCA), which represents police chiefs from the country's largest cities.

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He predicted over the longer term that police will increase surveillance and expand their security presence at major events across the country.

"This will cause complaints about violating people's constitutional rights to free assembly, but it is the only way to guarantee safety," he said.