Australia passed gun control measures in the wake of mass shootings there. The laws appear to have been quite effective in the years since: there have been zero mass shootings, and other indicators show that gun-related violence has decreased overall. The case for a connection between these things is quite strong. Of course, empiricism being empiricism, there's always room for questions about that. As well there should be. But questions are one thing, mangling another.
The Australian site The Conversation takes on the NRA's twisting of Australian crime statistics to try to prove the laws are in fact ineffective. Maybe it's because water swirls down the drain in the other direction down there (not true), therefore if it works in Australia, it would work in the opposite way here, see...
Perhaps the most blatant example:
The selective use of data, or cherry picking, is a commonly used method of extracting the “right” answer. This is true even when all the data tells a completely different story.
Cherry picking often exploits random fluctuations in data. Firearm deaths in Australia have declined over the past two decades, but from year-to-year one can see variations up and down. Bigger fractional fluctuations are likely if you shrink your sample size.
Leading US pro-gun lobby group, the National Rifle Association (NRA) was cherry picking when it’s publication, NRA News reported this statistic from New South Wales:
In the inner west, robberies committed with firearms skyrocketed more than 70% over the previous year, figures show.
Rather than giving the national trend over many years, the NRA chose one part, of one city, in one state and just two years of data. The NRA’s use of stats is misleading. Around Australia, robberies using firearms have declined from over 1500 per year in the 1990s to 1100 per year.
UPDATE: So there's that headline confirmed.