WGBH News reporter Adam Reilly's notes from the trial of James "Whitey" Bulger.

Today at the Bulger trial, we heard from Stephen “The Rifleman” Flemmi, Bulger’s former partner in crime and now a key witness in the case against him. 

Compared with Flemmi’s debut yesterday, which saw him and Bulger trade hostile glares and muttered epithets, much of today’s testimony was rather understated.

Not that the content was low-key: with its parade of gangland hits and corrupt FBI agents -- one of whom apparently gave the Winter Hill Gang a large supply of C-4 plastic explosives (!) -- many of the details were shocking.

But Flemmi’s demeanor, for most of the morning, was oddly subdued. Maybe he’s testified in so many other trials that this stuff has become rote. Maybe he’s totally devoid of anything resembling guilt. Or maybe Flemmi, who is 79, was just feeling his age. Whatever the reason, the majority of today’s proceedings didn’t pack much emotional punch. There were no new confrontations between him and Bulger, either. For most of the day, Bulger seemed to look at the desk in front of him rather than in Flemmi’s direction -- and after a few failed attempts to catch Bulger’s gaze, Flemmi seemed to give up.

Things changed, however, when Flemmi recounted the murder of his former girlfriend Debra Davis.

Prompted by Assistant U.S. Attorney Fred Wyshak, Flemmi recalled “blurting out” the nature of his and Bulger’s relationship with John Connolly, the corrupt ex-FBI agent who enabled the Winter Hill Gang’s criminal activities for years. Davis had grown frustrated at the frequency with which he was called away to late-night meetings with Bulger and Connolly, Flemmi said. So, in 1981, when Flemmi was summoned from a birthday party for a meeting by Bulger and Davis protested, Flemmi “blurted out” the nature of the relationship he and Bulger shared with Connolly.

Word of Flemmi’s revelation got back to both Connolly and Bulger, he said, at which point Bulger decided Davis had to die. Flemmi initially resisted, he claimed today. But Bulger talked him into it by noting that Connolly was too valuable an asset to compromise.

Describing the run-up to Davis’s murder, Flemmi briefly grew emotional, saying it’s affected him ever since, and will continue to “until the day I die.”

But his recounting of the murder itself was chillingly detached. Flemmi lured Davis to a house in South Boston and brought her inside. At that point, he recalled, “I couldn’t do it. So [Bulger] says, ‘I’ll take care of that.’ He grabbed her around the throat and strangled her.” 

Asked by Wyshak why he didn’t intervene, Flemmi said simply, “That was the plan.”

After the killing, Flemmi testified, Bulger “went upstairs and laid down” while he cleaned up the crime scene. They took off Davis’s clothes, wrapped her in a tarp, and took her away for burial in a makeshift grave, with Bulger watching while Flemmi and other associates did the digging.

“Why didn’t he do any of the work?” Wyshak asked. “That’s what he does,” Flemmi replied.

It won’t be the last we hear of Davis’s death. Bulger seems to have accepted much of the government’s case against him, but he’s determined to show that he didn’t kill Davis or Deborah Hussey, the daughter of another ex-girlfriend of Flemmi’s. When the defense crosses Flemmi next week, expect them to note that Davis was preparing to leave Flemmi when she was murdered -- and to suggest that Flemmi himself did the deed.