The 10 states with the lowest homicide rates are: North Dakota, Vermont, Wyoming, New Hampshire, Utah, Idaho, Iowa, Maine, Massachusetts and Oregon.
When you exclude the suicide rates and look only at homicides you get a VASTLY different picture. The following states on the list above received an F from the Brady Campaign (in their 2013 report): Maine, North Dakota, Vermont, Wyoming, Utah and Idaho. New Hampshire a D-, Oregon a D+. Iowa a C-, Massachusetts a B+. So 8 of the 10 states with the lowest homicide rates received a D+ or worse rating, and 6 received an F. In other words, states have a problem with criminals, not with guns. The controllers HAVE to lump in suicides to support their position, even though doing so is completely disingenuous because suicides and homicides have completely different causes and require completely different solutions.
Here's an article from Eugene Volokh that you should read:
https://www.washingtonpost.com/news/volokh-conspiracy/wp/2015/10/06/zero-correlation-between-state-homicide-rate-and-state-gun-laws/
The correlation between the homicide rate and Brady score in all 51 jurisdictions is +.032 (on a scale of -1 to +1), which means that states with more gun restrictions on average have very slightly higher homicide rates, though the tendency is so small as to be essentially zero. (If you omit the fatal gun accident rates, then the correlation would be +.065, which would make the more gun-restricting states look slightly worse; but again, the correlation would be small enough to be essentially zero, given all the other possible sources of variation.)