In Numbers 35:11 God instructs Moses to “provide yourselves with places to serve you as cities of refuge to which a manslayer who has killed a person unintentionally may flee.” The cities of refuge ensured the creation of the society cemented by the Divine law and not by the wills of different human beings.
In the case of unintentional manslaughter, the person seeking refuge was assured of the “trial before the assembly,” Torah is given to a rough and unforgiving society that yet cannot be trusted in taking care of the preservation of human life.
The following verses explain the difference between the murderer whom the avenger has a right to kill and a manslayer seeking refuge and protection until the trial.
Daat Zkenim here adds another dimension by saying, “…the Torah instructs the Jewish people to erect pointers guiding potential inadvertent killers with how to get to the nearest city of refuge at each juncture of major roads in the country.”
It is not enough to provide a place of refuge and sit there, waiting for the people to turn up. We have to signpost and advertise out shelters, whoever they might be designated for.