Democratic mayors of cities like New York, Baltimore, and Chicago must explain why their cities have frighteningly high and rising homicide rates despite strict gun-control laws. Their explanation is that guns come into their cities from surrounding areas where laws are less strict. But they cannot explain why these areas have lower homicide rates.

One way to establish a cause-and-effect relation is to draw a dose-response curve. That is, if you have more of A when you have more of B, then B may cause A. But if you have less of A when you have more of B, then clearly B cannot cause A.

This is the situation with these Democrat mayors. Their cities have stricter laws but more homicide. Surrounding areas have less strict laws but less homicide. From this a reasonable person would conclude that overly strict gun-control laws  do not prevent homicide. But an unreasonable person would conclude that we need even stricter laws. That is, we need more of what hasn’t worked. Passing yet more gun-control laws is thus a feel-good measure that is unlikely to accomplish anything – except to disarm and inconvenience law-abiding citizens. Let us at least make an attempt at logical thought.

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