Karen Read listens to the testimony of Cellebrite digital intelligence expert Ian Wiffin, during her murder retrial, in Norfolk Superior Court, in front of Judge Beverly J. Cannone, in Dedham, Mass., Monday April 28, 2025. (Pat Greenhouse/The Boston Globe via AP, Pool)
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Why 36 steps recorded by a health app could determine the Karen Read trial

In the Karen Read trial, a digital forensic expert for the prosecutor analyzed cellphone data from John O’Keefe’s phone. Read is on trial for allegedly backing her SUV into O’Keefe, her boyfriend and a Boston police officer, killing him. CNN’s Jean Casarez explains how the prosecution and the defense plan to use this cellphone data evidence.

01:34 - Source: CNN
US News 15 videos
Karen Read listens to the testimony of Cellebrite digital intelligence expert Ian Wiffin, during her murder retrial, in Norfolk Superior Court, in front of Judge Beverly J. Cannone, in Dedham, Mass., Monday April 28, 2025. (Pat Greenhouse/The Boston Globe via AP, Pool)
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Why 36 steps recorded by a health app could determine the Karen Read trial
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