First, fantastic job tracking down the actually relevant stats rather than the person above you who was trying to debunk.
Second - and this would only make your argument stronger and I’m not saying you needed to go this far - we would need to see if there has been an overall drop in crime rates. The tough on crime types love to tout numbers that reflect general trends as if they’re a justification or proof of the effectiveness of their policies. You need to demonstrate using proper statistical analysis to show that the falloff can accurately be attributed to a given policy.