Norfolk Superior Court Judge Beverly Cannone is sitting tight on deciding whether Karen Read’s defense can use its preferred dog bite expert in her second trial scheduled to begin in April.

After yet another marathon hearing to determine the fate of Dr. Marie Russell’s testimony in the retrial, Cannone took the prosecutors’ request to exclude the dog bite expert under advisement.

“She doesn’t have the qualifications, she doesn’t have the experience, she doesn’t have the methodology,” Special Prosecutor Hank Brennan told Cannone at the end of Tuesday’s hearing.

“But a willingness to tell opinions that are speculative, factually wrong, not based in science and math, should disqualify her from giving another baseless opinion about a so-called dog bite wound,” Brennan added.

Russell, a retired emergency room doctor at a Los Angeles-area hospital ranked in the top tier for trauma cases, maintained that in her professional opinion, dog bites caused the wounds to John O’Keefe’s body, and the related holes and tears in the clothing he wore on Jan. 29, 2022, the morning of his death.

Russell, who also worked as a forensic pathologist and medical examiner, continued to reject that a motor vehicle crash caused the wounds which is how the prosecution says Read killed O’Keefe, saying that none of them follow the typical patterns of a motor vehicle strike.

Brennan grilled Russell over the “standards” and “methodology” that she used in concluding that a dog caused the abrasions to O’Keefe’s right arm.

“You have personal experience in that you treated dog wounds and you’re looking at it and you’re simply deciding to you that this looks similar,” Brennan said to Russell. “You’re giving your personal aside, aren’t you?”

Russell responded: “I actually find that offensive.”

Minutes later in the heated cross-examination, Brennan suggested Russell was relying on her “subjective opinion.”

“With all due respect, Mr. Brennan, I’m not somebody who just came off the street,” she told him. “I have at least 30 years as a physician, and I use that information in helping me form my opinions about wounds. I’ve seen all types of wounds.”

Brennan then delved into whether Russell would alter her stance if she knew Read told Boston Magazine that “maybe John hit the back of her car telling her to stop, and that she ran over his foot or she clipped him in the knee, and in his drunkenness he passed out?”

“It wouldn’t help, because those wounds were caused by a dog,” Russell said.

Russell testified to the same opinion during the first trial that ended in the summer with a hung jury,

Prosecutors say that Read, 44, of Mansfield, struck caO’Keefe with her Lexus SUV following a night of drinking and yet another argument in their fraught two-year relationship and left him to freeze and die on the front lawn of 34 Fairview Road in Canton, where the pair were supposed to participate in an after party after the bars in town had closed.

She faces charges of second-degree murder, motor vehicle manslaughter while operating under the influence, and leaving the scene of an accident causing death.

The defense countered with their own theory of the case, positing that not only is Read innocent but that others are responsible for O’Keefe’s murder.

One theory they hinted at in the trial is that people inside the home, possibly including then-homeowner Brian Albert, a fellow Boston cop, beat O’Keefe to death and then used their influence in town to frame Read. They also said that Albert’s dog, a German shepherd named Chloe which the family has since surrendered, participated in the attack.

“If you ran an artificial intelligence program, you couldn’t come up with a more perfect witness for the subject matter of this testimony,” Defense Attorney Robert Alessi told Cannone. “The crucial issue of whether she is qualified, to me, is 100% in her favor.”

At trial, the defense had three other experts who also concluded that O’Keefe’s wounds couldn’t have come from a motor vehicle strike.

Brennan filed a motion Tuesday seeking to also block two of those experts, crash reconstructionists Daniel Wolfe and Andrew Rentschler, from testifying again in the second trial set for April.

The case will continue Jan. 31.