Anarchists usually think that a lot of murderers actually get away with it in our actual world, be it through war crimes, neglecting sanitary or safety rules to maximise profit; you can extend this list with a lot of legal murders.

Anarchism definitely does not define a specific rule for what to do with murderers. Different communities might want to handle that differently. They usually think that prison does not solve anything though, and that only the poor get sent there anyway.

I think a mistake is to think that anarchism is a “feature-complete” view of the world, when it really is the realisation that power corrupts, and that we should keep this in mind when organising ourselves. Arguably, over the long run, anarchist views are winning: institutions that prevent - in theory - crazy psychopath from taking absolute power, churches losing power over our lives, women considered as human beings; these are things anarchists have pushed for, for 2 centuries. This short essay might give you more insight: https://theanarchistlibrary.org/library/david-graeber-are-you-an-anarchist-the-answer-may-surprise-you

Let’s say you risk nothing if you murder. Would you start right away going on a killing spree ? Chances you think “I won’t but others will” and others actually think the same. An anarchist would probably analyse this by saying that destroying trust between indivuals living together is a basic tool power use to justify its domination. A pedantic anarchist would get his Latin out at this point. Divide et impera.

Anarchists tend to think that fear of the state is not the main reason why we don’t murder each other. In other words, following rules that are understood does not require the stick. Anarchists also tend to think that authority mostly enforce rules to maintain itself, and that the common good actually relies on something else.

Anarchy is not the absence of rules but the absence of authority.

Ass-to-ass.