Low income tax rates have a strong correlation with wealth-inequality within societies. Wealth-inequality in turn correlates positively with violence, low life-expectancy, infant-mortality, obesity,...
I had more about abusing data like this but just suffice to say this is a very poor argument. Once data abuse is treated like animal abuse our society will be getting somewhere. At that point it may even be possible for a government to spend tax money wisely rather than on wars and manipulating the economy.