1851-03-03: Congress sets up Board of Land Commissioners to judge private claims

"Following the discovery of gold in California in 1848, thousands of prospectors trespassed on Californio land and demanded the land for themselves. To determine the validity of Spanish and Mexican land grants in California, Congress set up a Board of Land Commissioners. Unless grantees presented in two years evidence supporting their title, the property would automatically pass into the public domain. Although the Land Commission eventually confirmed 604 of 813 claims, the cost of litigation forced most Californios to lose their lands. Government attorneys appealed 417 claims (out of 813). It appealed some claims as many as six times. Appeals dragged out land cases for an average of seventeen years."

http://www.digitalhistory.uh.edu/mexican_voices/voices_display.cfm?id=69

In California, Congress, by the acts of March 3, 1851, June 14, 1860, July 1, 1864, and July 23, 1866, provided machinery for the ascertainment and settlement of these claims, which has resulted in their final confirmation or rejection and in their subsequent segregation from the adjacent public lands. Questions of title were settled by the Federal courts, and authority to segregate claims judicially confirmed was vested in the proper executive officers of the United States.