From the AJC.com:
SAVANNAH — Four witnesses who testified against Troy Anthony Davis at his 1991 trial said Wednesday that none of their damaging testimony against him was true.
The witnesses, whose prior testimony helped put Davis on death row for the killing of off-duty Savannah Police Officer Mark Allen MacPhail, said they were pressured by authorities to point the finger at Davis.
At the 1991 trial, Antoine Williams testified he saw Davis shoot and kill MacPhail late one summer night in 1989 in a Burger King parking lot. But Wednesday, Williams said he was too scared to see who actually fired the weapon.