There have been some conflicts raised by this legislation, most notably the case of Kennewick man, where the direct descendants of the person/remains can not be certain. Kennewick man is the oft disputed set of remains that many argue is the remains of a caucasoid - i.e. a non-native, while other argue this really is a native's remains, and even specific tribes have claimed relation to these remains complicating things further.....
NAGPRA Database - " class="external">http://www.cast.uark.edu/products/NAGPRA/ "The American Indian community has argued that the remains of our ancestors could not be held legitimately or morally by institutions under any circumstances and should be reburied in a culturally appropriate manner by the appropriate religious body of a specific tribal group. For many Indian people, the position that scientific study needs to be conducted on these osteological materials does not carry much weight....If individuals of good will from the Indian community and scholars continue to enter into a positive dialogue on issues relevant to repatriation, we may eventually achieve an accommodation where both science and the interests of the native community can be served." George H. J. Abrams, Seneca, Anthropologist and Museum Director, 1998