Motive: complicated

The Associated Press has article about a (for once) righteous police shooting in Texas:

A gunman attempted to set the Mexican Consulate ablaze and fired more than a hundred rounds at downtown buildings before he died, Austin, Texas authorities said. Investigators were trying to determine the man’s motives after he began shooting at the consulate, Austin police headquarters, the US Courthouse, and other locations.
Some of the buildings are near the popular Sixth Street entertainment district, where bars close at 2 am, about the same time the shootings began. Austin police chief Art Acevedo noted that thousands of people are typically on the street at that time. “Many, many rounds were fired in downtown Austin,” Acevedo said. “With all the people on the streets, we’re very fortunate. I give thanks that no one but the suspect is injured or deceased.”
Mexico’s Foreign Relations Department issued a statement expressing “profound concern and condemnation” of the attack, but also said “there is no evidence the shots were exclusively directed at our facility”.
Acevedo said a sergeant, who was holding the reins of two police horses after his patrol, shot the gunman just outside the main entrance to police headquarters. But Acevedo said it’s not clear if police fatally shot the suspect or if he took his own life.
Police said the shooter was a man about fifty years old, with a criminal record. His identity was not immediately released, and Acevedo said investigators had not yet established a motive.
The shooter’s targets were located throughout downtown Austin and officers received multiple reports of gunfire. The entire incident lasted about ten minutes from the first call, Acevedo said.
Officers approached the man after he had been shot, but noticed cylinders in his vehicle, which was nearby, and discovered he was wearing a vest they thought may be rigged to explode. Officers retreated, and the bomb squad was called. It was later determined the items were not explosive. “Anytime you have cylinders like this with someone attacking government buildings, you have to think of explosive devices,” Acevedo said in describing the officers’ caution.
The suspect’s white van was still on the street outside police headquarters (photo) several hours after the shooting, with all its doors, trunk, and hood open while investigators looked it over.
The fire at the Consulate was extinguished before any significant damage was done to the building. The Federal Courthouse’s guard house was shot several times, as was police headquarters, which Acevedo said was “extensively damaged”.
The governor’s mansion is a few blocks away from the police station; it’s not known whether Governor Rick Perry was there at the time, and his staff did not immediately return telephone and email messages seeking comment.
A police tactical team later went to an Austin apartment complex where the gunman lived as precaution. The FBI also was participating in the investigation. Adam Peyton awoke to the sight of SWAT vehicles and police officers on motorcycles in his southwest Austin neighborhood near the city’s well-known Zilker Park. Authorities evacuated some of Peyton’s neighbors close to the apartment where the gunman is believed to have lived. Peyton described the area as “really laid back” and close-knit, where residents know each other and are often out walking their dogs. “As soon as they show his face, we’ll instantly know,” he said.

Rico's old friend Bill, who lives in Austin, Texas, notes that: "the part of the story I like is the officer holding the reins of two horses while he shot his sidearm with the other hand. Now that's cool."

Rico says that he and Bill agree that the horse thing's gotta be in the movie. (But, given the targets, the guy's motive is gonna be complicated...)