How much it shifted, where, and in which direction were the central issues in dispute, as both sides agreed that the Rio Grande, as it existed in 1850, was the true boundary.
As part of the Chihuahua Desert, lands in proximity to the Rio Grande were substantially more lush and fertile, and hence more valuable than similar sized tracts elsewhere in the region.
The Court appointed a special master to make findings of fact on the disputed issues in the case.
The Court heard oral arguments by both states in New Mexico v. Texas in 1927, and announced its verdict later that year.
They also implied that New Mexico had no standing to dispute any changes to its borders made before it gained statehood in 1912; those boundaries were an issue between Texas and the U.S. Federal Government.