Not just uncaught murderers, there are a lot of people who have killed without legally being considered murderers.
People who killed people in accidents such as driving accidents or hunting accidents
People who killed in self defense
Soldiers who killed enemy soldiers
Executioners
Police officers who have killed on duty
Doctors and nurses who have made mistakes that accidentally killed patients
I’m a nurse in a psychiatric hospital. When someone is actively suicidal, they indeed are not thinking straight. They are (usually) just looking for a way to escape their pain. Actively experiencing pain (be it physical or mental) reduces our capacity for empathy - that is, to consider how our actions will impact others.
I have had countless patients tell me their method/plan for suicide was to jump in front of traffic, jump from an overpass, lay on a road, lay on train tracks, etc… and none of them are ever, in those moments, thinking about how it will effect other people. Not because they wouldn’t care, but because they are simply unable to while in that state of mind.
I’ve had some who, once they were feeling better, shared about how they eventually realized how it would have impacted the driver of the vehicle (or the person who would find their body if it was by another method). But that usually only happens once they’re no longer actively wanting to die.
I’ve also had several patients who were the person to find a loved one post-suicide. It messed them up.