@Duxwing
Rational or not, they still made a decision. It doesn't matter what state they were in.
Making a "decision" implies rational deliberation, and we very well know that one can work another into a state, whether by words or drugs, in which rational deliberation, and therefore the ability to decide, is impaired.
Even if one was the most coercive and clever sun of a bitch on the planet, and reduced another to a squirming writhing mass of existential agony and compelled this person to suicide, the ultimate goal of the persons actions don't matter because he still does not exact direct control.
Oh yes it does. Human decisions-- not those of ideal agents-- are carried out in an actual piece of matter called "the brain," and the brain does not need to use its neocortex (the seat of reason) to effect motor response. Ways to prevent neocortical engagement include:
--All manner of psychoactive drugs
--Torture of all kinds
--Sudden, extreme stimulus
--Deliberate emotional manipulation
Psychoactive drugs, like alcohol, make people irrational, and therefore no longer responsible for their decisions; Torture prevents the use of executive function because the mind is too swept up in pain or fear to think; Sudden, extreme stimuli cause (both literally and figuratively) reflexive actions; And deliberate emotional manipulation can bring people back from the edge of suicide or murder (case in point, the people who do so for a living).
You can not compromise will even if you can compromise rationality. Rational or not the one who committed suicide made a decision to die. The reason for this decision is irrelevant.
A being whose will is controlled by an irrational mind cannot be held responsible for its actions: it's literally like having another person inside them, making their decisions for them. Let me draw you a picture of how healthy human stimulus-response cycles work so that we can understand each other's ideas better:
[STIMULUS]---->[SENSORY PREPROCESSING]---->[REFLEX CHECK]---->[RECOGNITION OF STIMULUS]---->[EMOTIONAL RESPONSE TO RECOGNITION OF STIMULUS]---->[RATIONAL DECISION]---->[EMOTIONAL RESPONSE TO DECISION]---->[MOTOR PREPROCESSING]---->[REFLEX CHECK]---->[RESPONSE]
If just one-- ONE-- of these parts of the cycle is removed or diseased, then the brain is no longer rational because it is either no longer using reason, not perceiving reality, not able to will itself to do what it wants to do, or a combination of the three; moreover, reflexes skip straight to [REFLEX CHECK], and the response cycle must be able to loop back on itself at any point lest the intermediate responses mean nothing. Rationality is an all or nothing deal.
To my knowledge, here's how your model works:
[STIMULUS]---->[RATIONAL DECISION]---->[RESPONSE]
In eliminating all the other parts of the stimulus-response cycle you've stretched the meaning of "decision" to irrelevancy.
-Duxwing