These words refer to the agreement by which one takes on the blame or credit for the results of an endeavour over which one has charge. Responsible is the most general of these words, suggesting not only such as agreement but applying beyond this to anyone who is mature or able enough to discharge difficult or exacting duties, to delegate authority wisely, and to perform capably despite unforeseen obstacles. More strictly it suggests the relationship between the performer of duties and his taskmaster: responsible to the people alone as to the adequate performance of his duties. It may also refer exclusively to the assignment of blame in a negative situation: a jury pondering over whom to hold responsible for the accident. Much more restricted in scope than responsible , liable refers exclusively to this last possibility of assigning blame; in a legal sense it can even refer, most strictly, to the payment of monetary damages in a mishap: laws that hold the driver liable for any injury to those riding with him.

Accountable , like liable , has a legal or technical sense, but in this case the word refers to the situation of stewardship in which the steward must demonstrate the wise use of things put in his trust: a departmental manager who is directly accountable to the directors for the funds allocated to his department. Answerable has a less technical ring to it than parents were to be held answerable for the widespread discontent of teenagers; evolutionary changes that are answerable to corresponding changes in the earth’s environment at the time of a species’ emergence.