Truth.

You can remove the qualifier from "socialist state" and it remains true.

Rummel's "Death By Government" details the twenty most murderous regimes of the twentieth century - https://cloudflare-ipfs.com/ipfs/bafykbzacecowyfyu2gxz4wwjdtthfv5cbsk5ar24o4k63er2dufcbrlngwet4?filename=R.%20J.%20Rummel%20-%20Death%20by%20Government-Transaction%20Publishers%20%281997%29.pdf

Of the twenty, only six were Communist (and one National Socialist).

Rummel found a trend towards less-murderous behaviour among democracies. I don't doubt it, but causality runs both ways - states strong enough to commit democide are strong enough to stop pretending to be democracies.

Among countries with more than 100 million people (my cutoff for functional independence), only the USA and Brazil have not been involved in democide.

I think its the privately owned guns not the check marks on ballots, but the sample size is too small to determine one way or the other...