They walked the landscape with surviving witnesses. They found a rock stained with the blood of the victim. They re-enacted the killings — here the U.S. Army Rangers swept through the canyon in their Humvee, blasting away; here the doomed man waved his arms, pleading for recognition as a friend, not an enemy.
"Cease fire, friendlies, I am Pat (expletive) Tillman, damn it!" he shouted, again and again.
The latest inquiry into Tillman's death by friendly fire should end next month; authorities have said they intend to release to the public only a synopsis of their report. But The Associated Press has combed through the results of more than two years of investigations — reviewed thousands of pages of internal Army documents, interviewed dozens of people familiar with the case — and uncovered some startling findings.
One of the four shooters, Staff Sgt. Trevor Alders, had recently had PRK laser eye surgery. Although he could see two sets of hands "straight up," his vision was "hazy," he said. In the absence of "friendly identifying signals," he assumed Tillman and an allied Afghan who also was killed were enemy.
Another, Spc. Steve Elliott, said he was "excited" by the sight of rifles, muzzle flashes and "shapes." A third, Spc. Stephen Ashpole, said he saw two figures, and just aimed where everyone else was shooting.
Squad leader Sgt. Greg Baker had 20-20 eyesight, but claimed he had "tunnel vision." Amid the chaos and pumping adrenaline, Baker said he hammered what he thought was the enemy but was actually the allied Afghan fighter next to Tillman who was trying to give the Americans cover: "I zoned in on him because I could see the AK-47. I focused only on him."
All four failed to identify their targets before firing, a direct violation of the fire discipline techniques drilled into every soldier.
Investigators have been stymied because some of those involved now have lawyers and refused to cooperate, and other soldiers who were at the scene couldn't be located.
Three of the four shooters are now out of the Army, and essentially beyond the reach of military justice.
Taken together, these findings raise more questions than they answer, in a case that already had veered from suggestions that it all was a result of the "fog of war" to insinuations that criminal acts were to blame.
The Pentagon's failure to reveal for more than a month that Tillman was killed by friendly fire have raised suspicions of a coverup. To Tillman's family, there is little doubt that his death was more than an innocent mistake.
One investigator told the Tillmans that it hadn't been ruled out that Tillman was shot by an American sniper or deliberately murdered by his own men — though he also gave no indication the evidence pointed that way.
"I will not assume his death was accidental or 'fog of war,"' said his father, Pat Tillman Sr. "I want to know what happened, and they've clouded that so badly we may never know."
And so, almost two years after three bullets through the forehead killed the star defensive back — a man who President Bush would call "an inspiration on and off the football field" — the fourth investigation began.
This time, the investigators are supposed to think like prosecutors:
The long and complicated story of Pat Tillman's death and the investigations it spawned began five years ago, in the smoking ruins of the World Trade Center.
"It is a proud and patriotic thing you are doing," Defense Secretary Donald H. Rumsfeld wrote to Tillman in 2002, after Tillman — shocked and outraged by the Sept. 11 attacks — turned down a multimillion-dollar contract with the Arizona Cardinals to join the elite Army Rangers.
The San Jose, Calif. native enlisted with his brother Kevin, who gave up his own chance to play professional baseball. The Tillmans were deployed to Iraq in 2003, then sent to Afghanistan.
The mission of their "Black Sheep" platoon in April 2004 sounded straightforward: Divide a region along the Pakistan border into zones, then check each grid for insurgents and weapons. They were to clear two zones and then move deeper into Afghanistan.
But a broken-down Humvee known as a Ground Mobility Vehicle, or GMV, stalled the unit on an isolated road. A mechanic couldn't fix it, and a fuel pump flown in on a helicopter didn't help.
Hours passed. Enemy fighters watched invisibly, plotting their ambush.
Tillman's platoon must have presented an inviting target. There were 39 men — including six allied Afghan fighters trained by the CIA — and about a dozen vehicles.
Impatience was rising at the tactical operations center at Forward Operating Base Salerno, near Khowst, Afghanistan, where officers coordinated the movements of several platoons. Led by then-Maj. David Hodne, the so-called Cross-Functional Team worked at a U-shaped table inside a 20-by-30-foot tent with a projection screen and a satellite radio.
(Hodne, now a lieutenant colonel and executive officer for the 75th Ranger Regiment, declined to be interviewed on the record by the AP — as did nearly every person involved in the incident.)
When the Humvee broke down, the Black Sheep were nearing the end of their assignment; all that was left was to "turn one last stone and then get out," Hodne would testify. The unit was then to head for Manah, a small village where it would spend the night.
The commanders had already given the Black Sheep an extra day to get into its grid zones. High-ranking commanders were "pushing us pretty hard to keep moving," said Hodne.
"We had better not have any more delays due to this vehicle," he told his subordinates.
At the operations center, the Black Sheep's company commander, then-Capt. William C. "Satch" Saunders, was feeling the heat to get the platoon moving.
"We wanted to make sure we had a force staged to confirm or deny any enemy presence in Manah the next day, so we would not get ourselves too far behind setting ourselves up for our next series of operations," he recalled later to an investigator.
The order came down to split the platoon in two to speed its progress.
Saunders initially told investigators that Hodne had issued the order, but later, after he was given immunity from prosecution, he acknowledged it was his decision alone.
Hodne later said he was in the dark — "I felt like the village idiot because I had no idea what they were doing," he recalled. The decision was foolhardy, he said. Divided in two, "they didn't have enough combat power to do that mission" of clearing Manah, he testified. (Other commanders have insisted that splitting the platoon was perfectly safe and a common practice.)
One thing is clear: The order sparked a flurry of activity by the Black Sheep.
One of the gunners who shot Tillman said his unit didn't even have time to look at a map before getting back on the road.
"We were rushed to conduct an operation that had such flaws," said Alders. "Which in the end would prove to be fatal."
"If anything, this sense of urgency was as deadly to Tillman as the bullet that cut his life short," Alders wrote in a lengthy statement protesting his expulsion from the Rangers. "We could have conducted the search at night like we did on the follow-up operations or the next morning like we ended up doing anyway. Why, I ask, why?"
An investigator, Brig. Gen. Gary M. Jones, would later agree that an "artificial sense of urgency" to keep Tillman's platoon moving was a crucial factor in his death: "There was no specific intelligence that made the movement to Manah before nightfall imperative."
An officer involved in the incident told AP there was, however, general intelligence of insurgent activity in this region, historically a Taliban hotbed.
That suspicion would be confirmed when the Black Sheep drove through a narrow canyon, its walls towering about 500 feet, and came under fire from enemy Afghans. Chaos broke out and communications broke down.
After the platoon split, the second section of the convoy roared out of the canyon, into an open valley and straight at their comrades a few minutes ahead. A Humvee packed with pumped-up Rangers opened fire, killing the friendly Afghan and Tillman, though he desperately sought to be recognized.
Later, at least one of the same Rangers turned his guns on a village where witnesses say civilian women and children had gathered. The shooters raked it with fire, the American witnesses said; they wounded two additional fellow Rangers, including their own platoon leader.
Had it happened in the United States, police would have quickly cordoned off the area with "crime scene" tape and determined whether a law had been broken.
Instead, the investigations into Tillman's death have cascaded, one after another, for the past 30 months.
For Mary Tillman, getting to the bottom of her son's death is more than a personal quest.
"This isn't just about our son," she said. "It's about holding the military accountable. Finding out what happened to Pat is ultimately going to be important in finding out what happened to other soldiers."
In the days after the shootings, the first officer appointed to investigate, then-Capt. Richard Scott, interviewed all four shooters, their driver, and many others who were there. He concluded within a week that the gunmen demonstrated "gross negligence" and recommended further investigation.
"It could involve some Rangers that could be charged" with a crime, Scott told a superior later.
Then-Lt. Col. Jeffrey Bailey — the battalion commander who oversaw Tillman's platoon — later assured Tillman's family that those responsible would be punished as harshly as possible.
But no one was ever court martialed; staff lawyers advised senior Army commanders reviewing the incident that there was no legal basis for it.
Instead, the Army punished seven people; four soldiers received relatively minor punishments known as Article 15s under military law, with no court proceedings. These four ranged from written reprimands to expulsion from the Rangers. One, Baker, had his pay reduced and was effectively forced out of the Army. The other three soldiers received administrative reprimands.
Scott's report circulated briefly among a small corps of high-ranking officers.
Then, it disappeared.
Some of Tillman's relatives think the Army buried the report because its findings were too explosive. Army officials refused to provide a copy to the AP, saying no materials related to the investigation could be released.
The commander of Tillman's 75th Ranger Regiment, then-Col. James C. Nixon, wasn't satisfied with Scott's investigation, which he said focused too heavily on pre-combat inspections and procedures rather than on what had happened.
Scott "made some conclusions in the document that weren't validated by facts" as described by the participants, Nixon would tell later investigators.
Nixon assigned his top aide, Lt. Col. Ralph Kauzlarich, to lead what became the second investigation. Kauzlarich harshly criticized Baker and the men on his truck.
Among other things, Baker should have known that at least two of his subordinates had never been in a firefight, and should have closely supervised where they shot.
"His failure to do so resulted in deaths of Cpl. Tillman and the AMF soldier, and the serious wounding of two other (Rangers)," Kauzlarich concluded. "While a great deal of discretion should be granted to a leader who is making difficult judgments in the heat of combat, the command also has a responsibility to hold its leaders accountable when that judgment is so wanton or poor that it places the lives of other men at risk."
Still, the Tillman family complained that questions remained: Who killed Tillman? Why did they fire? Were the punishments stiff enough?
"I don't think that punishment fit their actions out there in the field," said Kevin Tillman, who was with his brother the day Pat was killed but was several minutes behind him in the trailing element of a convoy and saw nothing.
"They were not inquiring, identifying, engaging (targets). They weren't doing their job as a soldier," he told an investigator. "You have an obligation as a soldier to, you know, do certain things, and just shooting isn't one of your responsibilities. You know, it has to be a known, likely suspect."
And so, in November 2004, acting Army Secretary Les Brownlee ordered up yet another investigation, by Jones.
The result was 2,100 pages of transcripts and detailed descriptions of the incident, but no new charges or punishments. The report, completed Jan. 10, 2005, was provided — with many portions blacked out or removed entirely — to the Tillman family. It has not been released to the public; the family found it wanting.
Pressed anew by the Tillmans, the Pentagon inspector general announced a review of the investigations in August 2005. And in March 2006, they launched a new criminal probe into the actions of the men who shot at Tillman.
The veteran Pentagon official who is overseeing these latest inquiries, acting Defense Department Inspector General Thomas Gimble, has called the Tillman probe the toughest case he has ever seen, according to people he recently briefed.
Investigators are looking at who pulled the triggers and fired at Tillman; they are also looking at the officers who pressured the platoon to move through a region with a history of ambushes; the soldiers who burned Tillman's uniform and body armor afterward; and at everyone in the chain of command who deliberately kept the circumstances of Tillman's death from the family for more than a month.
Military investigators under Gimble's direction this year visited the rugged valley in eastern Afghanistan where Tillman was killed. It was a risky trip; the region is even more dangerous today than it was in 2004.
According to one person briefed by investigators, the contingent included at least two soldiers who were there the day of the incident — Staff Sgt. Matthew Weeks, a squad leader who was up the hill.