Why was he so evasive during Police interrogation irrespective of whether you believe him innocent or guilty?
Have you ever been questioned by the police, Steve? Anyone who has, could tell you why you may avoid questions or make no comment. This is true regardless of guilt or innocence. The police when interviewing you already believe you to be guilty or you wouldn't be there. You are very aware that the questioning is designed to trap you and this makes you cautious.
Even if innocent this applies. A police interview is not some cosy friendly chat with tea and biscuits that you've popped along to because of the kind invite.
If you are innocent,especially on such a serious charge, many would be even more guarded.