If so, necessarily so. Not so much murder as the ability to make credible death threats is a huge source of power, in fact arguably the wellspring of all political power. A state cannot allow just anyone to have that kind of power. Humans are free while other domestic animals are physically constrained. This is generally true but the exceptions are revealing.
Humans gain physical freedom progressively through childhood as they become more trustworthy.
What's actually happening is that constraints on behaviour, both for our own safety and for that of society, are initially imposed physically, just as they are on non-human domestic animals but with humans these constraints are progressively internalised. Physical constraints are re-imposed. The amount of physical freedom is not speciesist. By implication to compare domestic animals with slaves assumes that non-slave humans are comparable to wild animals. We are domesticated animals.