I found what Disney says about photo copies
All Guests claiming U.S. citizenship must present one of the following as proof of U.S. citizenship:
A valid U.S. Passport
A valid U.S. Passport Card
A valid state-issued Enhanced Driver's License - this is a special type of license that provides proof of identity and U.S. citizenship; not all states offer Enhanced Driver's Licenses - visit
http://www.getyouhome.gov for the most up to date list of participating states
A valid Trusted Traveler Card (NEXUS, SENTRI, FAST)
Government-issued photo ID along with one of the following:
Original or copy of their state issued birth certificate
Puerto Rico birth certificates issued prior to 7/1/10 are not acceptable
Original Consular Report of Birth Abroad issued by the Department of State
Original Certificate of Naturalization issued by U.S. Citizenship and Immigration Services.
Guests under the age of 16 may present one of the following:
Original or copy of their state issued birth certificate
Original Consular Report of Birth Abroad issued by the Department of State
Original Certificate of Naturalization issued by the U.S. Citizenship and Immigration Services
With the exception of the state issued birth certificate, photocopies of the above documents are not acceptable. Hospital issued birth certificates are not acceptable proof of U.S. citizenship for purposes of traveling outside of the U.S.
Guests disembarking in a foreign port and not returning to the ship should be sure that they meet all of the documentation and entry requirements of that country. In addition, they may be assessed a fine or penalty according to local or national regulations.
But it says for guest under the age of 16. It doesn't say adults can.