The last one alone convicts him, frankly. That’s a million-to-one shot, conservatively. In the movie, Fonda dramatically produces a duplicate switchblade that he’d bought in The Kid’s neighborhood (which, by the way, would get him disqualified if the judge learned about it, as jurors aren’t allowed to conduct their own private investigations during a trial), by way of demonstrating that it’s hardly unique. But come on. I don’t own a switchblade, but I do own a wallet, which I think I bought at Target or Ross or some similar chain—I’m sure there are thousands of other guys walking around with the same wallet. But the odds that one of those people will happen to kill my father are minute, to put it mildly. And the odds that I’ll also happen to lose my wallet the same day that a stranger leaves his own, identical wallet behind at the scene of my father’s murder (emptied of all identification, I guess, for this analogy to work; cut me some slack, you get the idea) are essentially zero. Coincidences that wild do happen—there’s a recorded case of two brothers who were killed a year apart on the same street, each at age 17, each while riding the same bike, each run over by the same cab driver, carrying the same passenger—but they don’t happen frequently enough for us to seriously consider them as exculpatory evidence. If something that insanely freakish implicates you, you’re just screwed, really.