This is one of the graphs that Lott presented to the National Academy of Sciences Panel in 2002. David Mustard's originally included it in his contribution to Evaluating Gun Policy, but it was removed after Donohue showed him that it was the product of coding errors made by Lott. Later graphs produced by Lott look quite different---as we saw yesterday, this seems to be all the acknowledgment you get from Lott when he makes an error.
Notice how the graph shows crime rates falling sharply and immediately after carry laws were adopted. These results were much more dramatic than any that Lott has produced before. Even if the coding errors were accidental, Lott should never have presented this graph to the panel. It should have been obvious to him that the results were too good to be true, but because they seemed to support his thesis, he accepted them. Even if not dishonest, this is inexcusable negligence and casts doubts over all of his other research results.