LAWRENCEVILLE - Motherly instincts appeared to grip Vennie Davis when she looked to her son Wednesday and blurted from the witness stand: "I just wanted to say while I'm up here that he didn't do it."
Davis, 64, apologized after being warned by Superior Court Judge Timothy Hamil to not speak unless directly questioned, then she stepped from the stand with the aide of a cane.
Davis told jurors her son, Troy "Lee" Davis Jr., 43, was an obedient and adoring nephew incapable of harming her brother and sister, much less stabbing them more than two dozen times each.
The portrayal bore contrast to how the defendant's younger sister, Robin Coggins, 42, later painted his relationship with the slain elderly siblings, Lavader Chambers, 76, and Horace Marsingill, 79.
Lee Davis lived under Chambers' roof on Murphy Street in Buford - an address his aunt had called home since 1976 - for about seven years, the latter three with Marsingill living there also, Coggins said. He'd last held a steady job at a Checkers restaurant in the early '90s and earned some cash doing odd jobs like car repair, she said.
But jalopy cars began piling up in Chambers' backyard, along with unsightly woodpiles. Heaps of trash and discarded food accumulated in Lee Davis' room, Coggins said. The clutter caused a rift.
Chambers "worried about his room ... she thought there was probably mold" beneath the trash, said Coggins in the second day of testimony. "She was afraid to make him mad about it."
When the home incurred an ant problem, Chambers sprayed insecticide, though "Lee had a big issue with that," Coggins said. "He thought she sprayed it on his food intentionally."
Lee Davis was fond of his uncle, Coggins said, but an incident around Christmas fractured their relationship.
Prosecutors believe Lee Davis grew tired of the nagging and snapped on Feb. 28, 2005, fatally stabbing his aunt and uncle. He faces life in prison on multiple counts of murder and felony murder.
Lee Davis' attorneys argue he lacked a motive to kill. A collection of more than 20 knives was recovered in his room, but the murder weapon was never found.
Defense attorney Robert Greenwald used Coggins' testimony to drive the point that his client was a dim-witted social oddity. Dressed in an off-white shirt and blue, patterned tie, Lee Davis sipped from a water cup and stole long glances at the courtroom gallery.
"It would take him longer than some people to read ... and write," Coggins said.
Coggins tearfully recalled how, hours after the killings, Lee Davis showed no signs of remorse around his grieving family, saying, "I'm going to miss Horace - I liked him a lot," she testified.
Jury deliberations in the case could begin as early as today, an official said.