> They have the motive and opportunity but they lack the means

This seems to be a very confused application of evidentiary requirements. Before we talk above motive, opportunity, and means, we talk about the act itself. Every time a person bumps me on the subway when I have a pocket knife, I have motive, means, and opportunity to murder them, but unless I commit the act, that is not even the least bit interesting in terms of whether I am a murderer.