Skepticism about presumed consent in organ donor registration

Donate Life California posts a skeptical account of proposals to switch from opt in to opt out: An Attractive Concept with Unattractive Results

"72% of Californians and 75% of Americans who can become organ donors actually donate and save lives at the time of their deaths. Second,  California’s actual donation rate of 32.3 nDPM (normalized Donors per Million population[iv])  leads the US ‘s 26.1 nDPM and every country in the world except for Spain’s 33.5 nDPM[1] Meanwhile all other countries trail donation in California and the US; whether they have Presumed Consent or Explicit Consent laws."
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"Most significant in this assessment of PC vs EC is the fact that the European countries that developed and maintain presumed Consent in their laws do not rely on it to actually recover organs.  A 2012 survey of practices reports[vi] that donation professionals in all of these countries require family consent prior to recovery of organs. The fact that all countries that have PC laws do not actually rely on the right of the state to take organs speaks to the public trust and autonomy issues that arise when countries seek to claim any type of property, and makes it clear that the variance in donation rates is a function of cultural and operational aspects rather than legal characteristics of their donation programs."