Final answer:
California's legal system before the 20th century evolved from a feudal land tenure under Mexican rule to the American legal framework influenced by Roman law and the Compromise of 1850. It experienced significant land redistribution post statehood and underwent criminal justice reforms paving way to the modern legal system.
Step-by-step explanation:
The legal system in California prior to the 20th century underwent significant changes, especially during the 19th century. Initially, under Mexican rule, a feudal style land tenure system defined the region, with vast ranchos operated by a small number of families using indigenous and mestizo labor. Post the Mexican-American War in 1848, and as California transitioned to statehood in 1850, many of these landholdings were broken up due to unrecognised property claims or usurped by American interests.
The Compromise of 1850 marked California's entry as a free state, amidst the contentious national debate on slavery, having never been a formal territory. This era also experienced criminal justice reforms with a move away from public executions and a reduction in the number of capital offenses. California's legal landscape further evolved with the implementation of civil law principles and adoption of precedents influenced by Roman law, leading up to modern legal reforms such as the 'three strikes' law in the 1990s.