On that day, the dogs, two-year-old Argus and one-year-old Fiona, got out of their enclosed backyard when a tree branch fell and collapsed part of the fence, Mary Bock said. The dogs ran through yards of residences on the street behind them and ended up on the 72-year-old Pilotti's property, which includes a pen where he keeps sheep.
Around 11:30 a.m., Pilotti saw the dogs near his sheep, pulled out the 20-gauge single-shot shotgun he legally owns, and fired, said West Vincent Police Chief Michael Swininger. Mary Bock said police told her Pilotti first fatally shot Argus in the face, then shot and killed Fiona.
Police investigated and sent their report to the District Attorney's Office. That office has not filed charges against Pilotti, citing a portion of the Pennsylvania dog law that says, "Any person may kill any dog which he sees in the act of pursuing or wounding or killing any domestic animal."
That could change.
"We have gotten new information and are continuing to investigate," said First Assistant District Attorney Michael G. Noone, adding that a development could come Friday.
Mary Bock said she and her husband, William, were alarmed by what they saw as Pilotti's cavalier attitude. When William Bock asked Pilotti about the incident, his reply, according to the Bocks, was, "I shoot first and ask questions later."
He told police he had not even yelled at the dogs to chase them away before shooting.
The Bocks were even more outraged when they got a phone message recording from a neighbor whom Pilotti had called. On it, Pilotti says, "Hey, Bob, this is Gabe. Two shots, two more dogs."
The Bocks passed out fliers warning other pet owners in the neighborhood about him.
On Monday, William Bock posted a message on his Facebook page explaining what had happened to the dogs.
"It just kind of exploded from there," Mary Bock. said. Within 24 hours, more than 1,000 people had joined a Facebook page called Justice for Argus and Fiona.
The Chester County SPCA issued a statement condemning the shooting. And county resident Tom Hickey Sr., a member of the governor's dog-law advisory group, questioned the district attorney's reading of the law.
While Pilotti did not answer his phone or come to his door, next-door neighbor Robert A. Boden, a retired dentist, said his neighbor was being portrayed unfairly.
Boden called Pilotti a conscientious animal owner and a good neighbor. They have been friends for years.
About a year ago, Boden said, two pit bulls attacked and killed sheep and an alpaca in the neighborhood. Pilotti saw the attacks and shot the dogs.
For that, Boden said, "he's kind of a hero."
He said he had no idea what was going through Pilotti's mind on Feb. 12 but figures he was relating the dogs' presence to the earlier attack.
Still, Boden said, he does not condone Pilotti's actions.
"There were other alternatives than shooting them. . . . I think he did an injustice by shooting them," Boden said, adding that Pilotti had expressed regret to him about killing Argus and Fiona.
Mary Bock said the family had contacted State Sen. Andy Dinniman (D., Chester) to see if state law could be changed to prevent future killings.
Dinniman said he and Sen. Richard Alloway (R., Franklin) were working on a bill that would allow civil suits to be filed for up to $12,000 in the harming or death of a dog. Currently, dogs are viewed as a commodity and assessed only at their cost in lawsuits.
Back in the neighborhood, anger is bubbling over about the dogs' fate.
Boden said a woman went to Pilotti's house Wednesday night and screamed: "Dog killer! Dog killer!" and there are rumors that people might kill his sheep.
"What upsets me more than anything is that the dogs, the sheep, can be replaced, but now we have a people issue," Boden said. "I'm afraid somebody is going to do harm to somebody one way or the other over this."
Contact Carolyn Davis at 610-313-8109, firstname.lastname@example.org, or @carolyntweets on Twitter.
Inquirer staff writer Mari A. Schaefer contributed to this article.