Responsible: 1) acccountable, as for something within one's own power
2) having capacity for moral decisions and therefore accountable
Which brings us directly to the question of what is within one's own power. What is the capacity.
Are morality and freewill within one's own power to choose? To what extent are we capable of choosing.
Again, on Naturalism: Understanding causality. Multiple choice freewill. We're capable only to the extent we're aware of our options. And in that, perhaps, only accountable and responsible to that extent?
Steven Johnson's 2005 Mind Wide Open explores perception, how what we perceive determines our reaction. Most of it happening way beyond our consciousness; it's hard-wired response. Almost as though we don't have power to influence it. Only if one is AWARE of their perceptions and reactions to them, can they be altered.
Acting without regard to potential negative consequences would be expected to increase the likelihood of criminal behavior.
Prefrontal cortex activity is directly linked to abilities in "responsible decision-making and self-control." In that people may be limited in their capacity to take another's viewpoint and to empathize.
Without delving any further into this as it gets very mired down in explanation, I'll conclude in saying that there's a terrible shortage of self-awareness in human nature. And I believe, through chosen deliberate awareness, most can choose to do better. Even through a diseased brain. Perhaps not wet-brain or severe damage to the prefrontal cortex, but those are extreme exceptions. My experience with drugs that directly affect perception suggests to me that people have far, far more capacity to direct our actions and reactions than we actually engage.
Yet, despite that promising hopeful solution, most choose to remain unaware and blind to their options and actions. It's just easier to stick with preconceptions, convictions, beliefs.