Of all federal law -- because the Declaration states the principles which justify the existence of the federal government. The Declaration is the "constitutional fundamentals." Without the principles of the Declaration underlying the Constitution the Constitution is just an agreement a bunch of dead white guys reached two centuries ago, with no moral or legal authority over anybody. And the Declaration makes securing the unalienable (unable to be given away) right to life a central part of the very purpose of government, including federal government. Whatever debate we may have about the constitutionality of federal regulation of drugs, while there is such a law on the books, a federal officer cannot accept that prescribing suicidal drugs is legitimate medical practice, or legitimate at all, without repudiating the Declaration.
I asked you if the Oregon assisted suicide referendum contradicts the most fundamental principle of ANY federal law? -- And, - is this supposed 'law' based on any constitutional fundamentals?
Your answer was a backpedaled, moralistic no, just as I expected.
Life & liberty, as mentioned in the declartion, - are not religious concepts, they are political principles.