Anyone know what happens if some Bitcoins in the Pineapple fund turn out to be illegally obtained (theft, money laundering, ransom ware, drugs, etc.)? Is there any requirement for the donee to return the coins?
A different argument is based on property law[2]. You can't transfer better title than you have, but a "bona fide purchaser" obtains something that's practically pretty close to good title. So you could see the result hinging on whether a charity knew it was receiving stolen money (again, question whether property concepts apply at all to money).
[1]http://legalhistoryblog.blogspot.com/2013/05/reid-on-scotlan... -- OP didn't ask about jurisdiction, but this principle seems to be somewhat consistent in various places
[2]http://law.jrank.org/pages/9188/Personal-Property-Bona-Fide-...
Disclaimer: this answer is the product of law school, which means it is likely of even worse quality than a Wikipedia search.
The law doesn't concern itself with the technical implementation of bitcoin. In addition, trackable and "tainted" money is dangerous for people to accept; bitcoin just makes it real easy to identify that.
That's an astounding statement to make without citation or qualification. In general, the law (at least in the form of U.S. appellate courts and congressional bodies) is very good at including public-policy consequences in its decisionmaking process.
my point is that there is no guarantee that bitcoin will receive favorable decisions. it's hard for the lay person to understand (why not just print more?) and if ever declared a currency-non-grata could actively be attacked in this way.
i should add that i have engaged in btc currency speculation and had a positive result. the long term value/health of btc is of great benefit to me. but, it would be foolish for me to assume that because it would good for it to be so that it will be so.
The trustee of Mr. Madoff's estate sued a benefiting charity in 2009, in part "under the law of fraudulent conveyance" per which "there is a six-year lookback" for being "sued to return...money" [1]. (The chief problem with these lawsuits, the article notes, is the "traceability of the money." It remains to be seen whether Bitcoin's public ledger negates this problem of traceability.) They ended up setting for billions [2].
[1] https://dealbook.nytimes.com/2009/06/29/should-charities-rep...
[2] https://en.wikipedia.org/wiki/Jeffry_Picower#Involvement-wit...
Disclaimer: I am not a lawyer. This is not legal advice.