We don't "need" another "study" . . . especially on that can be "skewed" to achieve desired "result".
A good example of "skewed" results is that of marijuana . . . despite numerous studies showing the efficacy and safety of the substance, IT IS NEVER ENOUGH for those who don't like the "result".
We have seen the same situation with guns . . . despite numerous studies showing that "more guns (in responsible hands) equal less crime", it will never be enough for the gun-control crowd.