One thing seems clear about what happened in November outside the Overbrook home of District Attorney Seth Williams: Four tires were slashed on two security cars from his office.

That showed up 12 days later in a police report required by the city's Office of Fleet Management to replace the tires, at a cost to taxpayers estimated by the office at $845.64.

What remains unclear about the vandalism is who did it and why no investigation appears to have ensued to find out.

Was the daylight crime on Veterans Day, Nov. 11, a random act of violence? Retribution for a prosecution? A personal dispute?

If the district attorney knows, he won't say. Through his spokesman, Williams has declined numerous requests to comment on the matter. In response to a reporter's inquiries, his office issued a statement:

"For safety and security reasons, the Philadelphia District Attorney's Office does not comment or release details about matters involving the District Attorney's security or internal investigations."

Protection has been paramount for Williams since he took office in 2010. In six years, taxpayers have spent $2 million on a four-man security detail to protect him. Yet no money appears to have gone toward probing the tire-slashings, which left a curious paper trail through city records.

Two days after the incident, work orders were filed Nov. 13 with the Fleet Management tire shop to repair the left front and right rear tires on one of the city-owned cars, a 2008 Ford Crown Victoria, and the left front and left rear tires on the other, a 2010 Ford Escape.

Four days later, on Nov. 17, Sgt. Daniel Kearney, assigned to the District Attorney's Office Protection Unit, emailed a Fleet Management supervisor a number used to track the report of the damage.

In the email, Kearney apologized for a delay in providing the information and explained that he was waiting for a lieutenant to approve the report. Kearney's email noted that the office was investigating.

Estimates generated by Fleet Management on Nov. 17 put the cost of repairs at $437.82 for one car and $407.82 for the other, totaling $845.64.

Police incident reports routinely are generated as soon as officers arrive at the scene, and any investigation is assigned to a detective division within a day or two, police say.

But in this case, it was not until Nov. 23 - 12 days after the incident - that Kearney filed identical reports for the two cars, listing Williams' home address as the location. The reports list the cars by their assigned city property numbers. It is unclear from the reports whether Williams or the officers were there at the time.

"Below listed vehicles had damage to the vehicles and is under investigation at the Phila. District Attorney's Office," Kearney wrote, noting that the case would proceed under a different district control number - one that falls under Williams' office, not the Police Department.

Indeed, the Police Department is not investigating the tire-slashings, a spokesman, Lt. John Stanford, said in an email last week. "We don't currently have an active investigation on the incident," he wrote.

Under department policy, when a city vehicle is vandalized, an officer in the detective division where it happened opens an investigation. The incident at Williams' house was reported to the 19th District, but the file apparently was closed with no investigative follow-up.

Capt. Joseph Bologna, who runs that district, said he was unaware of the tire-slashings. His officers, he added, would have arrested anyone responsible for the vandalism at Williams' house.

After a reporter provided Bologna with the six-digit number attached to the police incident report, Bologna said the police paper trail stops with the incident report that Sgt. Kearney filled out. Williams' security staff probably needed to start with a 19th District control number to get Fleet Management to fix the tires, Bologna said.

Williams' predecessor, Lynne Abraham, said Thursday that no city security car ever was left parked outside her residence when she was district attorney.

"I was picked up and dropped off," said Abraham, who was in the job from May 1991 to January 2010.

Asked how a hypothetical tire-slashing of a city vehicle outside her home would have been handled, Abraham said the incident would have been immediately reported to the Police Department and investigated by the police detective division.

Meanwhile, four neighbors of Williams' said they knew nothing about the vandalism of his security cars. They said that no investigator had asked them whether they had seen anything unusual, and they described the neighborhood as safe and secure.

"It's very quiet here. We don't have traffic. Everything here is residential, and everyone knows everyone," said Diane Povine, 68, who lives a few houses from Williams.

"There's a town watch here," she said. "We have no worries."

Williams, 49, has made security a priority. On two recent mornings, a car belonging to the District Attorney's Office - a Ford Escape on one day, and a Crown Victoria on the other - was parked on the street outside his residence.

Last month, in response to a Right-to-Know request, the prosecutor's office provided the names of the officers assigned to protect Williams from 2010 through 2015, including their salaries and overtime.

But two weeks later, in a Feb. 19 letter, the open records officer, BJ Graham Rubin, requested "the return of the documents."

Rubin's letter said that to publish the names of the officers "is reasonably likely to result in harm and will compromise the safety of the officers, the DA and potentially the public in general."

The protection for Williams has cost taxpayers at least $1.9 million, ranging from $229,870 in 2010 to $376,580 in 2014. One of the four officers recently was reassigned.

By contrast, Abraham never had more than one police officer assigned to her security during her 19 years as the city's top prosecutor, she said.

"It was only one person. I didn't have a detail," Abraham, 75, said in a recent interview. "I had one person at a time."

Security for Abraham in 2009, her last year in office, cost taxpayers $99,436 for one officer, according to documents that Rubin provided.

Security for Williams last year amounted to a $361,186 tab for taxpayers - an increase of 263 percent over Abraham's figure six years earlier.

brennac@phillynews.com

215-854-5973

@ByChrisBrennan

Staff writer Aubrey Whelan contributed to this article.