A police chief once told Radley Balko the best way to pick a SWAT team. He told Balko you ask for volunteers and write their names down. Then you make sure those people are never on the team.

"Those are the last guys you want," the chief told Balko.

Balko, the investigative journalist and Huffington Post columnist who moved to Nashville from Washington, D.C., three years ago, says he is neither anti-SWAT nor anti-police. But he argues there is a time and place when that kind of force is appropriate — and with disturbing and increasing frequency, that line is being blurred.

In a troubling new book called Rise of the Warrior Cop, Balko tackles a subject of growing controversy in communities across the United States: the militarization of police forces. Drones, enormous armored transports, Army-issued helicopters — equipment manufactured for and used by the U.S. military in times of war is finding its way more and more into the SWAT teams of police departments across the country.

"This is just gear that was not designed for use in a civilian, domestic environment. It was designed for use on a battlefield," Balko says. "When you put on garb that was designed for a soldier to wear, it can and often does give you the mentality of a soldier or encourage you to assume that mentality."

Rise of the Warrior Cop recounts instances of botched raids from across the country. For one of many shocking examples, see this excerpt from the book, courtesy of PublicAffairs. Balko also traces the evolution of policing as a profession and the rise of the SWAT team from its origins in the civil unrest of the 1960s. "In most cities, the percentage of the police force that was white was completely disproportionate to the percentage of the cities that were white," Balko says, "and so increasingly you had police departments that couldn't identify with the people they were policing and that were psychologically isolated, physically isolated." Black demonstrators were seen not as fellow U.S. citizens deserving of the same constitutional and police protections but as enemy combatants whom the SWAT teams were formed to fight against.

"Then you have these riots going on and the racial divide," Balko says, "so I think that really was the start of this kind of battlefield mentality."

Rise of the Warrior Cop follows the entrenchment and intensification of that mentality, and Balko posits that the legalization of medical marijuana in California marks the real turning point in the misuse and overuse of SWAT teams. The deployment of these units in response to search warrants for marijuana as a part of the War on Drugs served as a way for the government to send a message to the people about how serious they were about this abstract war, Balko says, "regardless of whether those crimes actually present a threat to the community."

"In a free society, I think this is one of the more terrifying aspects of this trend, when the government starts using force to make political points. Until then, they had claimed that this kind of force was necessary because the drug dealers they were raiding were violent people who are ridiculously well-armed and love to shoot cops. There is reason to doubt all of those claims, but at least they were pretending," Balko says. "When they stopped pretending and started raiding hippie mom and pop medical marijuana dispensaries, that's when it got pretty scary."

Scary or not, the militarized police might have remained obscured in the shadows of the drug war had they not been drawn out into the streets by a new generation of rioters who were different in important ways from the ones who had inspired the formation of the first SWAT teams three decades earlier.

"I think what really got publishers interested in my book was the crackdown on the Occupy protests," Balko says. "Now you have basically upper-middle-class white kids that are getting beaten up, and these are kids who know how to stream video, know how to use social media to get the word out. ... They had some advantages that people who these tactics have traditionally been used against didn't have. It drew a lot of attention to the issue that otherwise wouldn't have gone to it."

But while the Occupy Nashville protests — or at least Gov. Bill Haslam's ad hoc dismantling of them — made national headlines, there is no mention of Tennessee in Rise of the Warrior Cop. Balko says he made a vow to himself when he moved here not to "do any bomb-throwing in my backyard." And while that declaration could be problematic if Nashville were a glaring example of jacked-up police power, a variety of sources corroborate that the Metro Nashville Police Department has done a decent job of staying committed to its goal of resisting a militarized mentality.

Even so, MNPD has procured its share of military gear from the federal government, including an armored vehicle, an MKII boat, a Zodiac inflatable raft, night vision cameras, M14 rifles, .45 caliber handguns and other "miscellaneous items" such as sleeping bags, cots, and camping gear.

Capt. Dhana Jones of the Special Operations Division asserts that despite the SWAT and Special Response teams using retired military equipment, "the officers aren't out in military gear or looking anything like the military." Jones says that Nashville's SWAT team has a "high level of integrity and professionalism." The SWAT team has 21 volunteer officers from across the department who go through an intense application and training process to become qualified members of the team. There are two training sessions each month that SWAT team members must attend. Jones says there are "special operating procedures we must abide by." For example, the department has a legal advisor who goes on scene with the SWAT team to ensure that everything they do "has legal standing." That advisor is also a practicing attorney.

"In Nashville," Jones asserts, "checks and balances are in place to mitigate a situation with as little force as possible and no mistakes."

The numbers appear to bear that out. In 2012, Nashville's SWAT team was deployed 120 times. Only 16 of these 120 included the entire SWAT team responding to barricaded subjects, in one instance with a hostage. The rest were "limited call-outs" where only part of the SWAT team was deployed: 36 for high-risk search warrants, 45 for equipment displays at community events, 18 for assignments such as training provisions, dignitary protection, high-risk arrests and special event response teams. So far in 2013 the SWAT team has been deployed 76 times. Only five of these have necessitated the full SWAT team, for barricaded subjects. None of these deployments appear on the CATO Institute's interactive map of "Botched Paramilitary Police Raids." There are six cases in Tennessee, the earliest from 1997 and the latest in 2004. Most involve the death of innocent people because of overeager SWAT teams that entered the wrong house. None of them happened in Metro Nashville. The closest occurred in 2000 in Lebanon, Tenn. — where the police own a seven-ton LAV-150 Commando reconnaissance vehicle. Four of the six botched SWAT raids in Tennessee were for drug warrants, something the Nashville SWAT team does not respond to except for "high-risk" instances where the suspect is thought to have weapons or known to be violent.

"It is true that at one point there was a lot of focus on military tactics adopted by the police," says Sgt. Robert Weaver, the Fraternal Order of Police president of Nashville's Lodge 5, "but recently most police departments have tried to embrace a community policing approach."

Both Jones and Weaver emphasize that they and their fellow police officers are citizens of this country, though perhaps it is easy for the public to forget that.

"We're citizen police officers," Weaver says. "We live and work in the community we serve. Most police officers are very aware and attuned to not wanting to live in a police state themselves. Despite the uniforms and despite the equipment, we're all just residents."

That equipment is changing, though. Along with its hand-me-down military gear, MNPD also recently received two Draganflyer X6 unmanned aerial vehicles, commonly known as drones, from a Department of Homeland Security grant. Kris Mumford, spokeswoman for the Metro Nashville Police Department, tells the Scene these six-rotor UAVs are not yet being used, as "the police department is still working on deployment strategies and usage plans that have to be approved by the chain of command." The Freedom From Unwarranted Surveillance Act, signed by Haslam on May 20, mandates that these drones cannot be used without a search warrant, with some exceptions. The same is true, in theory, of SWAT teams. Balko's book, due July 9, serves as a collection of cautionary tales about trusting such protections on their face.

Email editor@nashvillescene.com.