What if the flip flops had turned out to be key evidence in this case though? The police probably moved them and didn't note it because they thought it couldn't possibly matter. So who's to say that other things that the police didn't think mattered weren't moved?
You can only say that something proves his story a lie if the evidence is reliable. If the police wished to rely on their photo evidence they should have demonstrated that nothing, not even flip flops, were moved without it being properly noted and then recorded in the photos presented at court. They should also have called the first policemen to the scene surely.
If the flop flops were vital evidence and there was evidence of their inconsistent position then that could be called into question. There is no such questions regarding the fans, curtains, devet, so the evidence is reliable. Only a desperate guilty person would try to throw out all the photo evidence, because a pair of flip flops have been moved.