Vernier spotted a Phoenix police cruiser parked next to two paloverde trees near the north-side fence, about 15 yards from the tip of the "V."
He later told a detective that two things struck him as peculiar:
Vernier said police always back in near the end of the V, for safety reasons. But this cop car — a four-door Chevy Impala — had pulled in straight (tires slightly canted to the left), which meant the driver would have had to back up and turn around to leave the area, a basic tactical error.
("A cop's instinct is, don't ever, ever go in that way unless you're meeting someone," says Heston Silbert, a mentor of Drenth's at the Phoenix PD who now is Mesa's assistant police chief. "It is ingrained in you. It's about always being prepared for the fight. Sean always was prepared for the fight, believe me.")
Second, both front doors of the patrol car were open, another first in Vernier's experience.
"It looked weird to me," he said.
He parked his vehicle about 30 feet east of the police car, stepped out, and turned on his flashlight.
Vernier didn't see anyone at first and hollered "hello" so not to startle the officer.
He took a few steps forward after nobody replied and saw a uniformed officer on his back on the ground, just north of the patrol car.
The officer was still, and Vernier saw a large puddle of blood seeping from the rear of his head.
A onetime Army medic in Iraq, Vernier stayed cool. He immediately called in on his police radio and later told investigators that he didn't move any closer to the body before supervisors arrived.
It was 10:56 p.m.
"One of your officers has been shot at 18th Avenue and Jackson, just south," a Capitol Police dispatcher told a counterpart at the Phoenix PD. "We need officers and supervisors."
"Has he been shot, and did he shoot someone?"
"He's shot. My officer is saying he's dead."
Phoenix PD dispatchers had known for about a half-hour that Drenth didn't respond to officers trying to contact him.
One of many rumors that soon materialized was that the GPS unit inside Drenth's patrol car had been shut off before he died.
The rumor was not true.
A dispatcher issued an alert with Drenth's last GPS location, near 18th and Jackson, five minutes before Steve Vernier found the body.
Two Phoenix cops, Aaron Lentz and Clinton Swick, were working off-duty at a homeless shelter less than a mile east of where Drenth died.
They rushed to a police car after they heard the alert and were on their way there when a "999" call, the dreaded code for "officer down," came over the police radio.
Two of Vernier's supervisors arrived a minute or two before officers Lentz and Swick.
Corporal Nathan Clark approached the sergeant's body. He was the officer whose first reaction was that the shotgun on Drenth's body looked "staged."
Clark noted the officer's sidearm was missing from its holster and a snub-nose .38 was on the ground near the body.
Police handcuffs, a flashlight, and a cell phone also were splayed on the ground nearby.
Drenth's vehicle still was running, and Corporal Clark peered in to ensure no one was in it.
He and the other Capitol cops then retreated to await the arrival of the Phoenix PD. Lentz and Swick were the first from the agency to pull in.
Sean Drenth had stopped by the homeless shelter twice that night to see Lentz.
The first visit, at 6 p.m., was interrupted by a barricade situation that the sergeant had to cover. The second visit, for 40 minutes, ended about 9:30 p.m. — a little more than an hour before the "officer down" call.
Lentz later told Detective Brewer at the crime scene that he and Drenth just had been joking around at the shelter, nothing serious.
Brewer didn't yet know about the Lentz/Drenth connection in the off-duty security case (both men were about to be indicted) when he interviewed the officer that night.
But even after the detective finally did learn about the state investigation days later, he never re-interviewed Lentz about what the two men actually may have discussed at the shelter — the pending criminal case against them would have been an obvious topic.
Officer Swick, who wasn't present for much of Drenth's second, longer visit to the shelter, said he had bumped into Drenth as the sergeant was leaving about 9:30.
"He said, 'I'm gonna find some trouble to get into,'" Swick recalled.
What Aaron Lentz did at the crime scene that night continues to concern many people close to the case.
First, Lentz told Detective Brewer that he didn't immediately recognize Sean Drenth because of the trauma caused by the shotgun blast.