I hope only people of good character are reading this because I'm going to spill the beans about how a perfect murder might be committed. I call it perfect because in this scheme the law itself is the guarantor of the murder's freedom. It goes like this...
A man who we'll call Fred wants to kill his friend Joe. In order to do this he enlists the help of another man who looks just like Fred. The two look-alike Freds, wearing identical clothes, arrange to to be in public places at opposite sides of town at, say, noon the following day. It would help if the public places happen to have a large clock which displays the time.
At the appointed time each of the Freds, in opposite sides of town, loudly declares that he is Fred (using Fred's entire real name) and the real Fred shoots his victim, which I forgot to say was skillfully maneuvered to also be at the right place at the right time. The other Fred deliberately breaks a store window. Both the Freds make their getaway. Passer-bys will tell police that that they saw a man named Fred, who dressed in such-and-such a way, and will site the time, which was on a big clock. Can you see where this is leading?
Neither of the Freds can be tried for murder because each can prove he was somewhere else at the time. The police know that one of them did it but can prosecute neither since both Freds have an air-tight alibi! The murderer must be turned loose!
OK, that's my perfect crime! What's yours?