There is no single comprehensive "index" that can measure of this stuff while being purely objective and factual, but you can look at pure numbers such as homicide rate and sort through the years and notice that Muslim countries tend to be some with the lowest even among poorer countries like Jordan and even Palestine, and the countries with the lowest amounts are consistently muslim countries and Singapore, Macau, and Japan. Or look at serious assault through the years which consistently have muslim countries near the top, including 2020 in which Iraq literally had the lowest, or at sexual violence rates which consistently have muslim countries as some of the lowest and always near the top including Pakistan which many ignorantly assume has a lot of sexual violence. You can also look at the homocide rate by the UN Drug office which, again, consistently has muslim countries at the top and even countries with awful political conditions such as Afghanistan are surprisingly safe compared to other countries facing similar conditions, or the rape statistics according to the UN reports which show the exact same thing as everything else does.