Tyler was involved as a researcher and/or expert witness for several court cases in New Mexico related to Mexican land grants. Tyler labeled these as the Aamodt, Las Vegas, and Taos cases. More formally, they are New Mexico v. Aamodt, New Mexico v. Lewis, and New Mexico v. Abeyta. Files here document Tyler's involvement in these through court documents and his research papers. The files are in no particular order other than roughly grouped by case. Research subjects include land grants, water rights, acequias, the pueblo rights doctrine, and related laws. The series contains three confidential files closed to the public until fifty years from the date of creation; until then, they are open to clients involved or to others with written permission from the clients.