If anyone is falling prey to Simpson's Paradox, it's you. You're the one implying a causation based on those statistics. I'm asserting that there's not enough

If anyone is falling prey to Simpson's Paradox, it's you. You're the one implying a causation based on those statistics. I'm asserting that there's not enough information there to make any such connection, and I'm highlighting on the graph a short-term upward trend that contradicts the assertion that you are trying to make. Ignore that part of the data if it makes you feel better; I still wouldn't accept that there's enough data there to support your theory. Another interpretation of the data, also just a theory but no less valid, is that handguns rose in popularity as the weapon of choice within gangs, and the police responded by targeting gun crime. Again, I wouldn't want to state it as fact, but it would be a useful starting point for additional research. The reason frankly why I would need so much convincing that banning hand guns had any effect gun crime rates in the UK is because I just don't think there were enough gun owners to be statistically significant in the first place. Handgun shooting was a niche sport - a very niche sport.