What's the Difference Between D and a in This Case?

Nick had been in prison for nine years of his ten year sentence. It was overturned by the decision of a county circuit judge named patricia sullivan, who said that this case won't fly. She says that it's a violation of constitutional rights. After further examination, it was found that there was d and a, not amazing samples of d and a,. but dna that was from a male that was not nick and that evidence was not presented at the trial. So it was not known by the defence that there was another possible suspect, d and a present on major evidence in the case.