would it be an infringement of an individual's rights if we changed the donation policy that consent?

I am assuming this applies to organ donations and the like.

I think the big problem with implied consent for such is that how do you absolutely prove that someone has not refused to consent. Unless you cannot harvest the organs unless you have confirmed ID which would be tied to refusing consent.

I know plenty of states have organ donor things on their state ID's or drivers licenses. I wouldn't object to changing it so that you have to opt out through that rather than have to opt in to donate. As long as it is done openly and not intended to trick people into switching. This would make sure no one's body is disposed in a way that they would not object to, as they would have opportunity to opt out very clearly.