Updated: 3:03 p.m. 5/5/25

DEDHAM, Mass. (WBZ NewsRadio) — Another week of testimony is underway in the Karen Read murder retrial at Norfolk Superior Court in Dedham, Mass.

Read is accused of hitting her boyfriend, Boston Police Officer John O’Keefe, with her SUV and leaving him to die in the snow on Jan. 29, 2022. Read’s defense team has claimed she is innocent and is being framed.

Forensic Scientist Hannah Knowles Continues Testimony

Massachusetts State Police (MSP) Crime Laboratory forensic scientist Hannah Knowles returned to the stand when testimony resumed on Monday. Defense attorney David Yannetti started by cross-examining Knowles on her analysis of Read’s blood alcohol content (BAC) from blood drawn at Good Samaritan Hospital on Jan. 29, 2022.

Knowles testified that her conversion methods from serum to whole blood placed Read's BAC somewhere between ".14 and .28" on the night before O'Keefe's body was found. For reference, the legal threshold for operating under the influence is .08.

Yannetti questioned the wide range, Knowles' methods to determine it, and "assumptions" made about what time Read had her last drink. He also asked if she was requested to calculate BAC levels "of anyone except for Karen Read in this case." To the best of her knowledge, she said her unit was only asked to calculate Read's BAC.

Ryan Nagel Testimony

Ryan Nagel was the next witness called to the stand, who was at 34 Fairview Road in Canton, Mass., hours before O’Keefe’s body was found. He testified that he went to pick up his sister, Julie Nagel, who was there with her friend Brian Albert Jr. Nagel’s friend, Ricky D’Antuono, drove him to the house.

Special Prosecutor Hank Brennan asked Nagel about what he saw when he arrived at 34 Fairview Road. Nagel recalled seeing a woman sitting inside a black SUV. He testified that he never saw a man outside the house, or anyone exit the SUV.

Yannetti cross-examined Nagel about the drive over to the house, after he previously testified that the SUV was traveling ahead of them. Nagel said his friend Ricky appeared to be driving safely, as was the driver of the black SUV in front of them.

Heather Maxon Testimony

The third witness of the day was Heather Maxon, Ryan Nagel's ex-girlfriend, who was in the backseat as D'Antuono drove them to 34 Fairview Road. Maxon was drinking with Nagel and friends earlier in the evening and said she was impaired while riding to the house.

She testified that she saw a man and a woman inside a black SUV as they were driving over, but she did not know who they were. Once they arrived at the house, Maxon said she did not see anyone else in the SUV, which matched the description of Read's car, besides the driver.

Sarah Levinson Testimony

Sarah Levinson was the next witness on the stand on Monday, who was a friend of Julie Nagel and Brian Albert Jr. She was among those celebrating Albert Jr.'s birthday inside the 34 Fairview Road home in the hours before O’Keefe’s body was found.

Brennan asked her if there were any problems, arguments, or fighting inside the house throughout the course of the night, to which she responded no. When recalling who was inside the house throughout the time she was there, she did not name O’Keefe.

Defense attorney Alan Jackson handled cross-examination for the defense. He questioned her about the Albert’s dog, Chloe, who the defense has suggested may have something to do with O’Keefe’s death. Levinson said she had not met Chloe prior to Jan. 29, 2022, despite going to 34 Fairview Road several times.

Jackson asked Levinson about her interview with MSP Trooper Michael Proctor, the former lead investigator in the case. Levinson confirmed that was the first time she was interviewed by authorities, roughly nine months after O’Keefe’s body was found.

Canton Fire Department's Caitlin McLaughlin Testimony

Canton firefighter and paramedic Kate McLaughlin was next on the stand. She testified that she was one of the first responders at 34 Fairview Road and attempted life-saving measures on O’Keefe. Brennan asked her what she heard Read say that morning.

“I asked if there had been any significant trauma that happened that preceded this, and she answered with a series of statements that she repeated: ‘I hit him, I hit him,’ said McLaughlin.

McLaughlin went on to add that Read said the same phrase again to a woman next to them, who told Read to “calm down” and “stop talking.” When a police officer nearby asked Read what she just said, McLaughlin said she “repeated it again.”

During cross-examination, Jackson questioned McLaughlin about her relationship with Caitlin Albert, whose parents owned the 34 Fairview Road home. While admitting to socializing with Albert in high school and beyond, McLaughlin said the two were “not close friends” and only she saw Albert “in group settings.” She also testified she did not know it was the Albert's home when she was called to the scene.

Jackson played video footage from the morning O’Keefe’s body was found, which showed McLaughlin writing information on her latex glove. She testified that she was writing down “some of the things that were said,” but denied writing down anything about Read saying she hit him. Instead, she said she told the first responders back at the ambulance.

During redirect, Brennan asked McLaughlin why she did not try to get more information after Read said, “I hit him.”

“I felt bad for her at the time. It was a very disturbing scene and I did not want to push further down that road. It’s not my job and I did not feel comfortable doing it,” McLaughlin answered.

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NightSide with Dan Rea