The recipient of the fund’s donations would have to be constrained to only known-ethical effective charities, since otherwise you could “donate” through it to your personal trust and then withdraw from the emergency fund, or in a more unlikely case, the runners of an effective charity could “donate” through the fund to themselves, and then withdraw from the emergency fund.
Another problem is that if you care only about your chosen effective charity and yourself, you could donate $100 through the fund and then withdraw $95, which effectively means that you pay only $5 to donate $80 to your chosen charity. Someone who is doing this could essentially use the emergency fund as a 16:1 match on donations, which certainly isn’t the intended goal of it.
The recipient of the fund’s donations would have to be constrained to only known-ethical effective charities, since otherwise you could “donate” through it to your personal trust and then withdraw from the emergency fund, or in a more unlikely case, the runners of an effective charity could “donate” through the fund to themselves, and then withdraw from the emergency fund.
Another problem is that if you care only about your chosen effective charity and yourself, you could donate $100 through the fund and then withdraw $95, which effectively means that you pay only $5 to donate $80 to your chosen charity. Someone who is doing this could essentially use the emergency fund as a 16:1 match on donations, which certainly isn’t the intended goal of it.