Key witness Jennifer McCabe testifies Karen Read said 'I hit him' three times after finding John O'Keefe's body. Defense challenges inconsistencies in her account to grand jury.

A key witness in the retrial of Karen Read returned to the stand Wednesday for a second day of testimony, as she recounts the hours leading up to the death of Read’s boyfriend John O’Keefe – and the moment the off-duty Boston police officer’s body was found lying in the snow.