Your brother may wish to look at the case of State v Lujan, 71 P.3d 1286 (2003), in which the Court of Appeals of New Mexico addressed the "speedy trial" rights of a defendant who was incarcerated in California. That case discusses the rights of a defendant to a speedy trial under similar circumstances, as well as the application of the Interstate Agreement on Detainers (IAD) to this type of situation.
You can obtain the case for free on
LexisOne (free registration required). Go to "Find Cases For Free", click to "Search by citation", and enter the citation, "71 P.3d 1286".