A former girlfriend of Marcus Hurd, the sole survivor of the 2010 Mattapan killings, Tuesday contradicted Hurd’s sworn testimony that he identified Dwayne Moore as the shooter while the couple watched television together.

Tamara Cannon testified in Suffolk Superior Court where Moore’s defense attorney, John Amabile, is asking Superior Court Judge Jeffrey Locke to block Hurd from identifying Moore as the shooter during Moore’s upcoming first-degree murder trial.