I look at the house, and it's just another drab slap-up on a bland suburban street few will recall a hundred years hence.

Except for the video. Very likely, those images are enough to guarantee immortality. Because even in this Internet era, it is chilling to watch a man die.

So it is with Jose Guerena, who met his end in this house. Jerky footage shows us the forces arrayed against him: a SWAT squad huddling at the door, a quick knock, the door being bashed asunder, the fusillade exploding. Only later do we learn that the firefight is a one-way affair.

What we do not witness is the death grimace of the 26-year-old former Marine, a two-tour Iraq combat vet who just hours earlier had pulled a night shift at ASARCO's Mission Mine.

Nor can we quite parse fear, determination, exhilaration or anxiousness in the faces of officers assembled in that southwest-side neighborhood at 9:30 a.m. on May 5.

Later, we learn that, over some 30 seconds, they pumped 71 rounds into the home of Jose Guerena. The bullets ripped through nearly every corner of the house, including the bedroom where his wife, Vanessa, and their 4-year-old son cowered in a closet. Bullets tore through the back wall, pocked the yard's concrete wall and plinked the stucco of a next-door neighbor's home.

An autopsy eventually revealed that Guerena took 22 hits, some to the torso, but most to his limbs. He slowly bled to death on the floor. A robot was dispatched to prod his body. More than an hour elapsed before police let medics into the ravaged home.

Later that day, the Pima County Sheriff's Department issued a press release. "The SWAT team entered the residence and was confronted by Jose Guerena (26), who shot at them with an automatic AR-15 assault rifle," it read. "SWAT members returned fire, striking the suspect. Jose Guerena was pronounced deceased at the scene."

But in following days, that narrative gets hinky. We are told that, actually, Jose Guerena never fired a shot. This is a logical conclusion, given that the safety on his blood-specked weapon was never switched off. We learn that two years earlier, Guerena had been arrested on five felony counts as part of a federal drug investigation. Then we hear that the charges never stuck.

By May 18, the PCSD has issued another press release. "As a result of the need for information surrounding the shooting of Jose Guerena by members of the Pima Regional SWAT Team," it read, "the public has received misinformation and emotionally charged speculation.

"The investigation that led to the service of the search warrants on May 5 is a complicated one involving multiple people suspected of very serious crimes. Sometimes, law-enforcement agencies must choose between the desire of the public to quickly know details, and the very real threat to innocent lives if those details are released prematurely. ... The day the search warrant was served, we reported to the media that Mr. Guerena fired at SWAT officers. This is what was understood at that time. After a more detailed investigation, we learned that he pointed his assault rifle at SWAT officers; however, the safety was on, and he could not fire. This is a clear example of erroneous information being provided without careful investigation. Rather than risking the release of further information, it is imperative that we complete all aspects of this investigation.

"Since the Sheriff's Department has had such a long-standing practice of open and timely communication with members of the news media," the release continued, "it is understandable that questions are asked about when more information will become available. However, it is unacceptable and irresponsible to couch those questions with implications of secrecy and a cover-up, not to mention questioning the legality of actions that could not have been taken without the approval of an impartial judge.

"As a law-enforcement professional with decades of experience, Sheriff (Clarence) Dupnik will make the decision to release the information when the investigation is completed, the danger to innocent lives has been mitigated, and all agencies involved have been given the opportunity to review the actions of their personnel."

But then, on May 22, KGUN Channel 9 aired a report with Lt. Michael O'Connor of the Pima County Sheriff's Department describing the SWAT action. "As soon as we opened the door," O'Connor said, "they were confronted with an individual that was in a crouch position, pointing at them with an AR-15 military assault rifle and saying, I'll quote what he said, he said, 'I've got something for you.' And then they engaged this individual who was pointing this weapon at them."

Meeting with Arizona Daily Star editors on May 31, Dupnik described how Guerena and his relatives were the targets of a 20-month investigation into home invasions and narcotics-trafficking. Guerena's residence was among four raided that day in May. Inside his house, officers found body armor, a handgun, another rifle and a Border Patrol hat. The other raids turned up a tiny amount of pot, and a possibly stolen car.

As I write this six months later, Dupnik's investigation apparently continues. To date, there have been zero indictments against members of the Guerena family. I ask the Sheriff's Department about this, and Deputy Dawn Barkman tells me there will be no comment. So I check on the case with Kellie Johnson, chief criminal deputy attorney for the Pima County Attorney's Office. "Unfortunately, there's not a whole lot I'm going to be able to tell you about that," Johnson says.

Johnson does confirm, however, that her office "reviewed the shooting aspect of it, and cleared the officers of any wrongdoing."

On Oct. 31, Vanessa Guerena filed a $20 million lawsuit against Pima County and various law-enforcement agencies involved in the SWAT assault.

Today, many critics of the raid believe the investigation will never be completed, because there is no crime to solve, save the shooting of an innocent man. "They've made no arrests, because there were no arrests to be made, and there weren't from the start of this case," says Mike McDaniel, a 20-year law-enforcement veteran and former SWAT-team member. From his home in the Dallas-Fort Worth area, McDaniel now writes a conservative blog on police issues and other topics at www.statelymcdanielmanor.wordpress.com.

He's been fiercely critical of what he calls a "Keystone Kops" operation. "Now they're lying to cover up," he says. "They know this is a bad shoot—there's no question in my mind."

McDaniel sees two outcomes. One is that Vanessa Guerena gets a beefy settlement. "There will be the usual agreement that nobody speaks about it, and after a decent amount of time, it will have gone down the memory hole," he says.

The other possibility is that police "make a few token arrests. But even if they do, they're going to be embarrassing—you know, an arrest for possession of misdemeanor amounts of pot, and maybe one felony for car theft. That's basically all they've got."

Meanwhile, Dupnik's interminable investigation has only fueled skepticism—and an intense debate about the appropriate use of heavily militarized SWAT teams. It's a conflict that roars right across party lines, revealing ideological tensions between conservatives' distrust of government and their perennial embrace of tough law enforcement. Even liberals are split over support of police unions and a dislike of heavy-handed police tactics. Fair or not, SWAT teams have come to symbolize America's increasingly lethal brand of law enforcement—and the source of our uneasy national debate.

For some, such as Brian Miller, that conflict is up close and personal. In July, Miller was booted as chairman of the Pima County Republican Party after he openly criticized the Guerena raid. To him, growing police power—including military-style tactics—is the dark spawn of a decades-old war on drugs. But even questioning police tactics is considered blasphemous, he says, particularly in Republican circles. "Each side has their own blind spots. They want people to be free in one aspect, but not in another aspect."

According to Miller, many members of his own party tended to view the Guerena encounter as symptomatic of Tucson's poorer areas (although Guerena's neighborhood is decidedly middle class), and as something that only happens to other kinds of people. In other words, if you weren't part of the criminal underclass, you wouldn't find yourself face to face with a SWAT squad. "That's the dynamic that you deal with when you bring this up," he says.

Still, this is hardly a Republican-versus-Democrat issue, says Jeff Bumgarner, who has worked at all levels of law enforcement, from investigating crimes with the Federal Protective Service to serving as a small-town police chief. He's now a professor of political science and criminal justice at Minnesota State University in Mankato.

"It would be tempting to say that there's one party that's maybe more pro-police, and the other is maybe pro-civil liberties," he says. "But it's just not that simple. If you talk about unionized police, maybe that goes to one party or the other. Or you could be talking about regional issues, like in the South, where Democrats and Republicans alike are pro-police, and the Northeast, where maybe they are more suspicious of police. All of those things could be at work."

That certainly plays out in criticism of the Guerena case from otherwise staunch law-enforcement proponents. They include Richard Mack, the former sheriff of Arizona's Graham County, who's since become a nationally recognized gun-rights advocate.

Like a lot of folks, Mack contends that Jose Guerena would be alive today had uniformed cops, and not a hopped-up SWAT team, gone to the door. "It was a travesty that should have never happened," he says. "They shouldn't have had a SWAT team involved in that case to begin with. All law-enforcement agencies—and especially those in Arizona—need to re-examine the SWAT-team mentality. Why do we go and send SWAT teams on such mundane calls?"

To Mack, it's just the tail wagging the dog: Law-enforcement agencies "go to all this expense to have SWAT teams, and so they say, 'Well, we might as well use them.' You're talking about millions of dollars' worth of training and equipment. You have to justify having them, so you've got to use them. And most of the time, they are simply not justified or needed.

"If you get people dressed up for a dance," he says, "they want to go dancing. Same with SWAT teams: They're all dressed up. They have those guns. What do you think they're supposed to do with those guns? Just keep them on their laps?"

Mack won't get an argument from Mike McDaniel, who calls the Guerena case "a virtual textbook on how not to do things, not only in the execution of the raid itself, but also in the investigation—if you can call it that—that led up to the affidavit for the search warrant. I remain amazed that any judge would have authorized a search based on that affidavit. It's simply the most-incompetent thing I've seen in my life.

"Despite Sheriff Dupnik calling this a midlevel drug gang," McDaniel says, "and despite their long investigation, they admit in the affidavit that they had never even seen any of the suspects in possession of drugs."

That's true. The affidavit mentions the past narcotics violations of several individuals connected in varying degrees to Jose Guerena. It also provides a host of assumptions about the links between the individuals under surveillance—including Jose Guerena. But a thicket of conjecture does not a case make. And near the affidavit's conclusion, there is this: "During the ... surveillance concerning the aforementioned subjects," it reads, "they were not observed handling or even in the proximity of narcotics."

Here is McDaniel's take: The investigation puttered along for month after month, until closing it down—with no red meat on the table—was no longer a dignified option. "At some point," he says, "maybe after two or three months of this, a rational supervisor should have grabbed these guys and said, 'OK, what are your results with this investigation?' And when they said, 'Well, we've don't have jack; we haven't even seen any of them in possession of drugs,' the supervisor should have said, 'OK, enough of that crap. Let's move on to something new.' Well, apparently that was never done.

"I think what happened was that these guys had a year invested in this," McDaniel says, "and it came time to either put up or shut up. And rather than just shutting up and writing it off, and looking bad, they decided to go ahead with this thing. And once they decided that, Jose Guerena was dead."

Most experts trace the advent of SWAT teams back to Aug. 1, 1966, when a 25-year-old former Marine named Charles Whitman climbed atop a 307-foot tower at the University of Texas in Austin. Hunkered on the observation deck with three pistols and two rifles, he began to pick off people on the ground below. Soon, the Austin police arrived, and Whitman shot and killed a cop. Some 96 minutes elapsed before three policemen were able to scale the tower and kill Whitman. In the meantime, he'd murdered 13 people and wounded 31 others.

It was a watershed moment for law enforcement. "He essentially shut down the police department of Austin," says David Klinger, an associate professor in the department of criminology and criminal justice at the University of Missouri in St. Louis. "There was no way anybody else in the city could get any service, because everybody responded to that. Given the length of time it took, the whole place was paralyzed."

As a result, Klinger says, "some smart people looked at that and said, 'We need to have the capability to deal with these types of circumstances—guys with specialized training, equipment and so forth.' "

That same year, the Los Angeles Police Department, under an up-and-coming commander—and eventual chief—named Daryl Gates, formed what appears to be the nation's first special weapons and tactics unit. This SWAT team proved useful in ensuing years, such as when L.A. police battled the radical Symbionese Liberation Army in a massive shootout.

Parallels between tactical police units and the military are hardly just coincidence, Klinger says. "My understanding about the first SWAT teams in Southern California is that a sizable chunk of those guys were military veterans. But a sizable chunk of police throughout the country at that time were military veterans."

Since then, the SWAT presence has only grown. "In the last 20 years, there's been a recognition that SWAT teams play a major role in law enforcement," he says. "Instead of the stepchild we're going to keep in the basement, there is a recognition that they play a vital role, and you really need to have them around."

Yet even today, there's no national training standard, Klinger says. "It's very uneven around the country. Unfortunately, that means some places will throw together a bunch of guys, give them some guns, put them in cool uniforms, and say, 'Now you're a SWAT team.' "

At the same time, the units are given plenty of legal latitude. "If a SWAT team is doing its job, then they are not a liability, because they're behaving in a reasonable fashion," Klinger says. "That's the standard in federal court: Was the officers' behavior reasonable given the circumstances?

"On the flip side ... if you have a SWAT team where you don't have sound oversight," he says, "where you don't have sound management, a SWAT team can be a liability."

Klinger points to the case of Jesse Runnels, a 25-year-old man with emotional problems who was shot and killed by a Miami police officer in 1999 after allegedly brandishing a toy gun. The shooter, SWAT team officer Alejandro Macias, was accused of lying to investigators. "Apparently, he tried to cover up the shooting, because it wasn't kosher," Klinger says.

Only three years earlier, Miami police defended themselves in the shooting of 73-year-old Richard Brown, a narcotics suspect who died in a barrage of 123 bullets when a SWAT team invaded his apartment. The city ultimately paid a $2.5 million settlement to Brown's great-granddaughter, who was in the apartment at the time. The deal came after a city attorney judged the police statements to be contradictory and implausible.

In 2001, five veteran Miami cops were indicted by a federal grand jury for conspiring to obstruct justice by fabricating evidence and lying to investigators, in an attempt to justify the Brown shooting. They included Macias, the same officer who killed Jesse Runnels.

In 2004, Macias was acquitted of lying in the Runnels case. A year earlier, he was also among three SWAT officers acquitted in the Brown shooting. However, a total of four other Miami cops were convicted in 2003 of covering up police shootings in a variety of incidents.

"The point is that you essentially had a rogue outfit where these guys were doing things like planting guns," Klinger says, adding that such abuse is obviously not limited to SWAT teams. "It can occur with a drug unit that isn't following proper procedures or detectives who are forcing false confessions from murder suspects.

"So to say that a SWAT team in and of itself creates a liability problem, no, it doesn't. But if you don't have appropriate oversight, and these guys are coercing confessions, then you've got liability."

The courts, however, take a broad view of police shootings. According to Jeff Bumgarner, two pivotal U.S. Supreme Court decisions redefined the view of police force. One involved a young burglary suspect who was shot and killed by police. In that 1985 case, Tennessee v. Garner, the court ruled that a Tennessee statute authorizing the use of deadly force against any fleeing subject was unconstitutional, unless the subject posed a serious threat to officers or the public.

Four years later, the court reviewed Graham v. Connor, involving a man who was detained and roughed up by police who thought he'd robbed a nearby convenience store. But there had been no crime committed, and the man later sued. While the court sided with Graham, it also reaffirmed the "objective reasonableness" standard under the Fourth Amendment.

"Not only is deadly force a seizure issue, but any use of force is a seizure issue under the Fourth Amendment," Bumgarner says. "But what's interesting about the Graham case is that the court said, 'It's important that we look through the eyes of a reasonable officer at the time.'

"That's where the court really foreclosed on Monday-morning quarterbacking of police actions. Just because it turns out that police were mistaken doesn't mean their actions were unreasonable in that split-second of the time, with the information the officers knew at the time.

"Officers aren't expected to absorb a couple of rounds before they make a decision," he says. "I think that most officers are trying to do the right thing. But they also want to make sure that they go home at night."

But this comes at a cost: As police struggle to keep up with the bad guys, the military countenance of SWAT teams can distance them from the community. "I think there is that potential," Bumgarner says. "It certainly doesn't give off the image of Officer Friendly."

Perhaps sensing their contentious public persona, tactical units themselves seem to be taking cover. Repeated requests to observe SWAT teams in action at the Southern Arizona Law Enforcement Training Center on South Wilmot Road were denied. So were several requests to interview SWAT-team commanders. That certainly contrasts with reporting I did in the 1990s, when SWAT teams were not only open about their work, but proudly squired me around their elaborate training facility, complete with a mock town for practicing home entries and other maneuvers.

It could be a sign of our secretive, security-obsessed era. "We certainly see trends over time around here," says Sgt. Matt Ronstadt, a spokesman for the Tucson Police Department. "And for whatever reason—and maybe for a variety of reasons—the current feeling (among SWAT commanders) is that they need to keep their tactics closer to their vest."

Or perhaps Guerena residue lingers. "It's entirely possible," Ronstadt says. "I know that for some time after that case, there was a lot of interest in our team and what our folks do and how we go about handling business. The feeling at that point was that we were going to stay out of those interviews, because of the pretty significant potential pitfall of ... looking like we were second-guessing what happened at that scene."

The Tucson Police Department now has a retired tank that is at least occasionally stored at the city's Thomas O. Price Service Center on South Park Avenue. In its salad days, this hunk of rolling armor was a military-personnel carrier. Post-retirement, it became TPD's SWAT-team evacuation vehicle. "It was also used a number of times as a rolling shield for SWAT operators, in order to get them into a better tactical position," Ronstadt says.

The tank has a twin on the other side of town, and since both are government leftovers, the city "probably got them on the cheap," he says, "probably for a buck or something like that, one of those surplus offloads."

But given the growing cost to maintain these aging vehicles, and the fact that they're quite cumbersome on the road, TPD eventually put them out to pasture. They've been replaced with a $280,000, armored tactical truck purchased with a grant from the U.S. Department of Homeland Security. "That's used to transport SWAT operators to an operation someplace—to a warrant service or what have you," Ronstadt says. The department also has a SWAT equipment truck, which is "essentially our mobile storage locker."

The standard long gun for TPD SWAT-team members is a Colt Commando, a 5.56-mm, .223-caliber carbine short-barreled rifle with an optical sight that's either a magnifying scope or a combat-type, red-dot sight for close quarters. SWAT snipers have their own rifles, which have been the Remington Model 700.

Some officers are specially trained in using explosives for breaching entries. There are trained medics. The SWAT unit has 39 members culled from throughout the department. That includes one supervisor and three officers assigned solely to SWAT. Others are detectives or patrol officers who have SWAT as a secondary assignment.

For TPD, there have been 170 SWAT operations in the past fiscal year, up from 163 the year before. The majority of deployments are to serve high-risk search warrants or protect dignitaries. The department spends around $30,000 annually for ammunition and less-than-lethal munitions.

The Pima County Sheriff's Department didn't offer detailed expenditures for SWAT, saying that much of the manpower comes from difficult-to-calculate overtime. According to Deputy Dawn Barkman, most of the training is funded by grants, as is equipment such as ballistic shields, vests and a robot. As with TPD, the Sheriff's Department uses its SWAT teams for high-risk warrants and hostage situations.

Mike McDaniel considers SWAT teams to be self-perpetuating creatures, with economics defining how—and how often—they are used. For instance, he says it can cost $2,000 a year per man just for ammunition. A good marksman's rifle can cost up to $5,000. Night-vision equipment? Tack on a few grand more. And that's just the start.

"They're very expensive to establish and equip and maintain and train," he says. "So once a community or county has forked over the money for this thing, and sees it as a continuing budget item ... once you've got them, there's pressure to use them. So people end up using them in situations where they shouldn't be used."

After he was ousted by the county GOP, Brian Miller didn't spend much time licking his wounds. Formerly an Air Force major, he's now in the Reserves. And he doesn't regret talking about his stance on the shooting death of Guerena. If anything, his criticism has grown more trenchant.

"What you have is an accusation, after a (long) investigation of a guy who's supposedly the muscle in a midsized drug ring," he says. "He has a wife and two kids and a mortgage. He also works from 6 p.m. to 6 a.m. at a mine. Therefore, he's doing his drug-muscling between the hours of 2 and 4 p.m. in the afternoon."

Miller considers this case emblematic of a national phenomenon, in which far too much police force is used far too frequently. "I am critical of the policy that puts law enforcement at people's doors this often with this much firepower," he says. "You don't have to look any further from the 54-second video released by the Sheriff's Department to realize that this was an ill-trained, ill-disciplined group of heavily armed agents that had no business delivering lethal force."

He likewise predicts that Vanessa Guerena's lawsuit will expose the ugly truth. And to Miller, that truth is this: "If it wasn't murder at the end of those 72 shots, an hour and 17 minutes later, when they didn't give Jose Guerena medical support—yeah, that's murder.

"In my opinion, Jose Guerena had to die. Because with what happened that morning, there was no room—as far as the Pima County Sheriff's Department was concerned—for the other side of the story. He had to bleed out."

Today, the splintered front door of the house once inhabited by Jose Guerena and his family is secured by a heavy padlock. The rear wall reveals bullet holes, each precisely marked by analysts. One window is broken and gaping. A child's scooter sits forlornly in the abandoned dirt yard.

The tidy, tile-roofed neighborhood seems asleep as I go next door and ring the bell. Robert Peterson answers. He is a retiree with a trimmed white beard who tells me he moved there in August, so he knows little about Jose Guerena or the shooting. Oh, his real-estate agent did mention something. And one day about a month ago, some men were taking odd measurements in the Guerenas' front yard. But that is all.

"It's quiet here," says Peterson, a friendly fellow in socks who could have been disturbed from his afternoon nap. "The only thing we hear is the barking dogs."

The afternoon sun glances through thick mesquites as I thank Mr. Peterson for his time, and leave this peaceful place that erupted like hellfire on May 5.

If there are answers to be found, they will not be found here.