In the US, suicide is "legal" in the sense that it's not technically a crime. But attempting to do it or even talking about doing it can get you imprisoned against your will and/or forced to take mind-altering drugs without your consent. Also, anyone trying to help you with it can be charged with a crime. So I'm using the term "allowed" instead, to get around its sham legal status.
This market resolves to YES if someone can decide they want to die and then make it happen without significant inconvenience. Otherwise it resolves to NO.
A few exceptions that will still allow this to resolve YES:
Children and others who are considered by society to be "unable to consent" may still be prevented from committting suicide without the consent of their guardian. But if those guardians do consent, the suicide must be allowed.
It's ok if there's a required period of reflection where the person is asked to think things through and make sure they aren't acting rashly, and/or talk to a therapist. That period must be a month or less, and the person must not be forced to take any drugs.
It's ok if the suicide must be supervised or happen in a certain place or way, such as to make sure it actually was suicide and not murder. But it must be easy for the suicidee to get to that place and to set this set up.
People who plausibly do not know what the words mean (young children, adults with severe mental disabilities) don't count as wanting to commit suicide if they express such a desire via words, but it does count if their actions clearly show they're trying to die.
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But if those guardians do consent, the suicide must be allowed.
This is the part I'm most confident will not happen. It's hard to imagine a US state allowing a child to commit suicide with parental consent (which could be exploited by abusive parents who regret having had the child).
@adele If the child is so young that they might not know what the words actually mean, I won't count that. A 5 year old saying "I want to die" because they heard it on the TV and their mother saying "yeah ok" is obviously no good. But a 17-year-old who has actually thought it though and discussed it with their parents should be allowed.
@jack If the suicide is only allowed contingent on some ternimal disease, that's no good, market will count that towards NO.
Theoretically, if it were easy to walk up to a doctor and ask them to sign off on your assisted suicide and the majority of them would just do it, then that would resolve this market to YES. But if most doctors are going to withhold such agreement contingent on a factor like serious disease, that's not good enough.
@IsaacKing makes sense, what about e.g. https://en.m.wikipedia.org/wiki/Euthanasia_in_Switzerland where I believe there's no specific reason required?
@jack On paper, that system seems like it would resolve this to YES. But I'm concerned that it might be harder in practice.
For example, what does this mean?
Swiss law only allows providing means to commit suicide and the reasons for doing so must not be based on self-interest (such as monetary gain).
Does this make it illegal for companies to sell a means of suicide, and it can only be given for free?
the major Swiss nonprofit organisations dedicated to assisted suicide may require that a terminal illness has been diagnosed.
That's awkward too. It doesn't sound like those organizations are a necessity, but maybe in practice they are.
And just like in the US, the fact that it's legal to commit suicide doesn't mean there aren't penalties for expressing intent. If you walk into a doctor's office in Switzerland and tell them you're depressed and want to kill yourself, are you going to be able to walk out of your own volition?