In the United States v. Baca case of 1901, the Supreme Court ruled on a dispute over land ownership in New Mexico. The plaintiff, Juan Estevan Baca and his family claimed that they were rightful owners of a tract of land under an old Spanish grant which was recognized by Congress in 1860 but later revoked due to fraudulent practices discovered during surveying process. However, Bacas argued that their claim predates this fraudulence as it was established before the Congressional Act and should be upheld regardless. The U.S government disputed this claim arguing that since the original grant had been annulled due to fraudulence, all subsequent claims including those made by Bacas are nullified too. The Supreme Court sided with Bacas ruling that while indeed there were fraudulent activities associated with some parts of the original Spanish Grant; not all sections within it were tainted hence legitimate claims such as those made by Bacas could still stand independently from invalidated ones. This decision set precedence for future cases involving property rights especially where historical or ancestral grants are involved; affirming that each section within a larger grant can be treated separately based on its own merits or demerits rather than collectively punishing or rewarding them based on overall status of entire grant.

The dissenting opinion in the United States v. Baca case argued that the government did not have sufficient evidence to prove its claim of ownership over disputed land. The dissent emphasized that the original Spanish grant, which was later recognized by Congress, clearly gave title to Baca and his descendants. It pointed out inconsistencies in how similar cases had been handled previously and questioned why a different standard seemed to be applied here. Furthermore, it criticized the majority's reliance on an 1860 survey map as proof of federal ownership when there were doubts about its accuracy and completeness. The dissent also expressed concerns about potential negative impacts on property rights if such weak evidence could be used successfully by the government to assert claims over private lands.