Pamela Bozanich had served as Deputy District Attorney in the early 90s when she took on the disturbing murder trial of Lyle and Erik Menendez, stating that she never believed the brothers’ claims about suffering unspeakable abuse at the hands of their father — and won’t start now. “This is not a manslaughter trial. Erik and Lyle were not victims,” she declared in an upcoming docuseries, RadarOnline.com can report. The siblings were convicted of killing their parents, Jose and Kitty, with a shotgun in Aug. 1989. Erik and Lyle soon told police that an intruder had killed their parents before pr…