AUBURN – A week-and-a-half before her death, Melissa Mendoza told a friend she would shoot Daniel Roberts if she had a gun, a defense witness testified Tuesday.

Instead, it was Roberts, 37, who shot and killed Mendoza, 29, his ex-girlfriend. He claims she pointed a gun at him, threatening him and their 2-year-old daughter Savanna before he shot her in the back of the head in self-defense at his Sabattus home.

On the 10th day of Roberts’ murder trial, Jamie Bolduc of Lewiston told an Androscoggin County Superior Court jury how angry Mendoza had become toward Roberts in the months leading up to her death. Bolduc said she had witnessed several of Mendoza’s jealous rages that culminated in assaults on women. She also became consumed by her on-and-off boyfriend, talking constantly about Roberts, using coarse language and yelling at him during phone calls, Bolduc said.

Mendoza often stayed with Bolduc in her finished basement when Mendoza was in Maine and on the outs with Roberts, Bolduc said. She also often looked after Savanna for Mendoza. Eventually, Mendoza wasn’t allowed to stay with Bolduc, she said, because the rift between the couple was taking a toll on her family.

Bolduc also testified that Mendoza came back from California one time with the word “Daniel’s” tattooed on her pubic area.

In early August 2005, Mendoza walked into Bolduc’s house “very upset.” She told Bolduc: “‘If I had a (expletive) gun, I would shoot him,'” referring to Roberts, Bolduc said.

Bolduc said she had witnessed several of Mendoza’s violent acts.

She had been at a Lewiston dance club with Mendoza a year earlier. She told Bolduc she would be right back. Mendoza walked up to a woman and “just attacked her,” Bolduc said.

That woman, Nadine Gendron, also testified Tuesday.

Gendron said she had dated Roberts more than a dozen years earlier. The two remained friends, and Gendron had lately agreed to help Roberts with his credit by reviewing his finances. The two met weekly at Gendron’s Lisbon Falls home for dinner.

On April 1, 2004, Gendron said she was with friends at the former Rock’n Robin’s dance club in Lewiston, hoping she might see Roberts. She had worn a T-shirt she ordered as a joke to play on Roberts, who vowed he would never marry. The front of the white shirt bore the words, “Mrs. Roberts.”

Mendoza “appeared out of nowhere” at the club, Gendron said, wearing a tan trench coat. Mendoza grabbed Gendron by her long hair and pulled her to the floor. She punched the woman and wrestled with her for one or two minutes, Gendron said. A couple of bouncers pulled Mendoza off her, Gendron said.

After the fight, Mendoza told Bolduc that: “She’d be the only (expletive) Mrs. Roberts if there was gonna be a Mrs. Roberts,” Gendron said.

She also testified that Mendoza had broken into her home earlier, scattering Roberts’ financial papers. Mendoza once tailgated Gendron in her car through a cul-de-sac, Mendoza’s arm extended out the window, her middle finger up, Gendron testified. In addition, Mendoza sent Gendron vulgar e-mails, expressing Mendoza’s possessiveness of Roberts, Gendron said.

One of the e-mails said, “‘Stay away from my man,'” Gendron testified.

Bolduc recalled another time she went to a dance club with Mendoza. That evening also ended with Mendoza fighting another woman.

The summer of 2005, Bolduc said she pleaded with Mendoza to go back to California and wait until it was her time to take custody of Savanna. Mendoza refused, Bolduc said.

Defense attorney Leonard Sharon called several witnesses who told how Mendoza began to drink more heavily as time went on. She became more agitated and consumed by Roberts, they said. The women assaulted by Mendoza said they told him of Mendoza’s aggressive actions.

Roberts’ mother, Pauline Fraser of Greene, testified that at Savanna’s birthday party she was with her son at his bedroom closet while he was changing his shirt. Mendoza walked in, Fraser said.

Roberts asked her, “Where’s my gun?”

Mendoza answered, “I put it up here,” pointing to the closet shelf.

When cross-examining Roberts’ mother, Deputy Attorney General William Stokes asked what prompted Mendoza to come into the bedroom at that time.

“Did he call to her?”

“No,” Fraser said.

After answering Roberts’ question about the gun, Mendoza turned and left the room, Fraser said.

Deputy Attorney General William Stokes questioned the credibility of several of the defense witnesses, seeking to cast doubt on their testimony Tuesday that differed from statements made to Maine State Police detectives after the shooting.

When first interviewed, Bolduc never told police about Mendoza’s statement that she would shoot Roberts if she had a gun, Stokes pointed out.

Bolduc explained that she kept it from police on purpose until three months after the shooting because she initially didn’t want to repeat Mendoza’s words without Mendoza present to put them in context.

Stokes asked Bolduc whether Mendoza ever threatened to shoot or harm Savanna.

“Never,” Bolduc said.

Stokes asked Gendron whether she ever told police about any of the incidents involving Mendoza, including the break-in, which she said prompted her to install deadbolts on her doors.

Gendron said she hadn’t.

The defense is expected to wrap up its case by the end of the week, Sharon said Tuesday.