Ex-con charged in 4 murders in North Carolina Town

This attack on Sunday looks like a possible multiple victim public shooting.  From Fox News:

Marcos Chavez Gonzalez was charged with four counts of murder in the slayings late Sunday outside Woods TV in Mount Airy, about 100 miles north of Charlotte, police said. . . . 

Police do not believe the shootings were random, but Mount Airy Police Chief Dale Watson said they did not plan to release a motive. . . . 

"I'm not sure it's totally sunk in because it's so unusual. On any given Sunday there is nothing here in this parking lot. There's nothing here at all," he said. "My biggest question is why in this parking lot at all. Why Woods TV parking lot?"

UPDATE (11/11/2009): Apparently, this attack may be somewhat more complicated than it first appeared.  The involvement of two other individuals, who probably knew of the crime and Gonzalez's involvement given all the media attention, may suggest that this may be some type of criminal enterprise.

Police in North Carolina say two more suspects have been arrested in connection with the shooting deaths of four people in the town used as the model for Mayberry in "The Andy Griffith Show."
Mount Airy police say 56-year-old Kathy Young Barnette and her son, 34-year-old Gregory Brandon Holt, were arrested Tuesday in Patrick County, Va. Authorities said Barnette and Holt live in Claudeville, Va.
The suspects will be extradited to North Carolina, if needed, where they will face charges of accessory after the fact to murder. Police in Mount Airy said four men were killed Nov. 1 when someone opened fire at a television store there. Police do not believe the shootings were random, but Mount Airy Police Chief Dale Watson said they did not plan to release a motive. . . .

Gonzalez's past criminal history that appears to go well beyond his past conviction for kidnapping (felony kidnapping of a minor and his listing as a sex offender), a probation violation, and his previous deportation is also consistent with a criminal enterprise.  Most importantly, it also does not appear as if Gonzalez had any legitimate form of employment at the time of the attack.  At this point, it is too early to tell what exactly happened here.

Note if this is indeed the case, that the attack was part of gang or drug activity, it would be excluded from the instances that Bill Landes and I have collected.  From our paper:

We excluded multiple shootings that were byproducts of other crimes (e.g., a robbery or drug deal) or that involved gang activity (e.g., drive by shootings), professional hits or organized crime. We also did not count as a multiple shooting serial killings or killings that took place over the span of more than one day.  There are two reasons for excluding these types of multiple shootings.   

First, since shall issue laws permit law-abiding citizens to carry guns, they should have little impact on killings related to gang activity, drug deals and organized crime. Putting to one side, injuries to bystanders, individuals involved in gangs, drugs and organized crime are already engaged in unlawful activities that often require them to carry guns.  Their behavior will be largely independent of whether a law on the books permits or prohibits citizens from carrying concealed handguns. Hence a “right-to-carry” law should not impact whether gang members or drug dealers are armed or kill each other. . . . 

UPDATE: The attack was apparently part of some gang or other crime activity: press conference two months after attack discusses this:  "a 'contract killing,' or whether it was gang- or drug-related."