The anti-2nd Amendment prohibitionists are running their traps right now about how "America" has a gun problem. In reality, the murder rate overall (ALL weapons including firearms) in the US is at a 50 year low, while the number of firearms and conceal pistol licenses are at an all time high. That does not necessarily mean that the CPL's are stopping murders, although one can argue that. It does mean that more guns does not increase the number of murders.
About 2 1/2 years ago, the Center for Michigan, a left-leaning group, ranked the number of CPL's per capita for each county. One of the things I do for my work is to look at data, read it, and find out what's going on out there.
I compared the murder (and non-negligent manslaughter) rates (per MSP) for each Michigan county over the last five years. I used the 2014 census estimates for population. I used a five year average because there are some fluctuations in each year. A bad year (my county in 2013 had 5) or a good year (my county in 2012 had none - and I believe 2015 is at zero so far) can skew data.I haven't done this for every state, but at least in Michigan, there is no correlation between the number of CPL's and number of homicides. The correlation is that three counties have the most homicides, by a large number.
12 Counties had no murders in the past five years. That includes numbers 1 (Keewenaw), 4 (Oscoda), 8 (Mackinac), 10 (Dickinson), and 15 (Luce) in CPLS, along with number 72 (Leelanau). All of those 12 counties are in Northern Michigan and similar culturally.
11 Counties had an avg rate between 0 and 1 per 100,000 over a 5 year period. Most of these were also small counties including CPL ranks 9 (Lapeer), 13 (Roscommon), and 14 (Iosco), but also included Ottawa (CPL rank 82), Eaton (28), and Allegan (65) Counties. Ottawa's low rate would even be lower if it wasn't for a bad 2014 with 5 homicides after 4 in the previous 4 years.
17 counties had an avg rate between 1 and 1.5 per 100,00 over a five year period. These were mostly small counties, but also includes Macomb (Cpl rank 51), Livingston (CPL rank 12), and surprising to me, Berrien County (CPL rank 79). Macomb and Livingston's data were skewed by two aberrations. Livingston would have had a rate of under 1 if it wasn't for 2013. Macomb only had one murder in 2012 after having 10-15 the other four years (although still would have had a rate slightly under 1.5 with an avg 2012). Shiawassee (CPL 19) and Delta (CPL 20) are in this category.
1.5 is comparable to Canada's rate (1.44). Livingston (1.18), Macomb (1.16), and Berrien's (1.28) rate are lower than Canada's. The most recent I've seen for Australia is 1.3.
35 Michigan counties had a murder rate lower than Australia and 40 have a lower rate than Canada, favorite comparisons used by prohibitionists (which never use Mexico's 21.2 rate as a comparison). That is out of 83 counties.
13 counties had an avg rate between 1.5 and 2. These were mostly small counties, but include Bay (CPL rank 52), St Clair (CPL 21), and highly fluctuating Washtenaw (CPL 81). High CPL counties here are Alcona (3), Gladwin (11), Ogemaw (16), and Lake (20). Those four had 1 or 2 homicides over the past five years, but low populations skewing them to the middle of the pack.
16 counties had a avg rate between 2 and 3. These included Oakland (CPL rank 41), Monroe (CPL Rank 31), and Kent (CPL rank 83). Alger (CPL 5) and Crawford (CPL 17)are high CPL counties in this category skewed by population as they had one and two murders in the past five years.
Four counties had an avg rate between 3 and 4. These were Ontonagon (CPL 24) , Benzie (CPL 47), Kalamazoo (CPL 77), and Muskegon (CPL 75). Ontonagon was skewed by population as it had one murder in five years. Benzie had 3, but a small population. Kalamazoo and Muskegon are larger counties and fluctuate, although the rates are increasing a bit in Muskegon.
These are all well below the US average (around 4-5).
Those around the avg 4-5.2 are Montmorency (CPL 2), Ingham (CPL 78), Calhoun (CPL 36), Jackson (64), Schoolcraft (CPL 6), Gogebic (68), and Iron (CPL 7). Population skewed Montmorency, Schoolcraft, Gogebic, and Iron counties as all four of those counties averaged less than one murder in a year. Calhoun County had a bad 2012 impacting its numbers. These are still all around the average of the US, but high for Michigan if you measure by median county. They are all lower than the Michigan average - which is skewed by three counties.
The three counties with significantly high rates are Saginaw (cpl 17), Genesee (CPL 27), and Wayne (CPL 45) Counties. Saginaw's rate is 9.23, Genesee's 12.73, and Wayne's 19.69 (which is still lower than Mexico). Wayne County alone has 61% of the murders (and 17% of the state population). Genesee has 9.3% of the murders and 4% of the population. Saginaw has 3% and 2% of the population. Almost 3/4 of all the homicides murders in these three counties.
The lesson for this is that America - at least most of America - does not have a gun problem. A handful of counties and communities have a murder problem. You take these communities out of the equation, and the murder rate is little different than Canada or Australia. The commonality isn't the guns.