BRATTLEBORO, Vt. — For many who frequent the Brattleboro Food Co-op, getting wine advice from Richard Gagnon was a pleasing ritual. His knowledge was encyclopedic, and after years as the store’s wine manager, he was a fixture in the homey downtown store.

But Gagnon’s tenure ended abruptly one morning last month when, according to the police, he walked into the office of Michael Martin, his boss, and fatally shot him in the head. Gagnon, 59, was charged with first-degree murder and is being held without bail.

That this murder would happen in Brattleboro, a magnet for artists, hippies and healers in the southeast corner of Vermont, was unusual enough. But murder in the co-op, an organic grocery store that is owned by its members and committed to democratic principles, was beyond reckoning.

"It’s not Walgreens or Price Chopper or Hannaford’s," said Kelly Salasin, a member from neighboring Marlboro. "It is something that belongs to us, and there’s a sense of responsibility. It’s as if a murder happened in your own family."

According to a police affidavit, Gagnon had received a poor performance evaluation from Martin, who was also 59. He shot Martin with a semi-automatic handgun just after 8 a.m. on Aug. 9, the police charge, as the co-op opened for the day and employees stocked shelves. The police say he then walked outside and dropped the gun, saying, "I don’t want to hurt anyone else."

In meetings, online forums and conversations in the aisles of the co-op and other gathering spots, people here have struggled to understand how Gagnon could have harbored such anger. And they have wondered how the co-op, with its focus on community and utopian ideals, could have missed signs of it.

"There’s a part of me that feels a little shameful," said Aimee Denette, 31, who works in the co-op’s bulk foods department. "Now there’s this very weird energy in the co-op because, I mean, someone was murdered here."

Others say that energy has infiltrated the entire town of 12,000 over what has been a troubled year. In April, a five-alarm fire tore through a historic downtown building, displacing more than 50 residents. In July, a young woman who had been living here was found dead in a wooded area outside town, apparently the victim of a drug-related murder.

Then came the co-op shooting and, weeks afterward, the devastating floods that accompanied Tropical Storm Irene, which ravaged dozens of homes and businesses, displaced more residents and left crucial roads in tatters.

But more than the other misfortunes, the co-op shooting made the community scrutinize itself. Many of the co-op’s 5,600 active members felt compassion not just for Martin, a four-year employee, but also for Gagnon, who had worked there for two decades.

Some fondly recalled the descriptions he wrote for various wines — "No one understands the vagaries of making good sauvignon blanc like the denizens of the Loire," went one — while others have racked their brains for any signs they might have missed about his mental state.

"A lot of us knew Richard rather well," said Judy Price, a longtime co-op member. "That’s the mystery around here — he did such a good job with that beer and wine department, but there could have been other issues under the surface that we didn’t know about."

According to the police affidavit, the performance review Gagnon was carrying at the time of his arrest raised issues about his relationship with other co-op employees and his management style. The review warned that Gagnon could lose his job if the issues were not addressed.

A co-worker of Gagnon’s told the police that co-op managers had been urging Gagnon to resign because of the "hostile atmosphere" he created, the affidavit said.

On Monday, a state judge set a deadline of Dec. 31 for Gagnon’s lawyer to disclose if he plans to seek an insanity defense.

In a posting on her blog, This Vermont Life, Salasin recalled chatting with a fellow shopper on her first visit to the co-op after the shooting. "What must have he been going through to do what he did?" the woman asked, referring to Gagnon.

The co-op reopened two days after the shooting and has returned, more or less, to its usual pace. It held an apple tasting recently and, on Sept. 9, exactly a month after Martin’s death, a wine tasting.

"We have so many people here who are very aware — socially, emotionally and spiritually," Denette said. "If something like this had to happen in a workplace, I’m glad it happened in a place like this."

Meanwhile, in what many consider propitious timing, a project is under way next door: a new, more spacious co-op building with affordable housing units on top, scheduled to open in April. The old building will be demolished.

"It kind of feels good, honestly," Salasin said. "But I don’t believe you can get rid of things."

She added, "This will be part of our story."

© 2011 The New York Times Company