Final answer:
The first informal law enforcement agencies evolved as part of the need for early governments to enforce laws and maintain social order, with ancient China providing one example. In the United States, such agencies developed post-Civil War with the creation of the Department of Justice to uphold federal laws, leading to more formal law enforcement structures.
Step-by-step explanation:
The establishment of the first informal law enforcement agencies can be traced back to various parts of the world where centralized governance began to take shape. Early governments required methods to enforce laws and maintain public order, leading to the creation of administrative structures that often included officials responsible for these tasks. In ancient China, for instance, the territory was divided into commanderies and counties with magistrates appointed to oversee legal enforcement, tax collection, and public works.
In the United States, after the First Enforcement Act was passed by Congress, President Grant established the Department of Justice under Attorney General Amos T. Ackerman to uphold federal laws and prosecute violations. This was an early version of a federal law enforcement agency. By the time of the Second and Third Enforcement Acts, mechanisms and agencies were created to supervise elections and extend the federal government's authority to enforce civil rights and counteract voter intimidation and violence.
Additionally, local law enforcement in North America can trace its origins back to elected representatives, such as the burgesses in 1619, who established the rule of law for their communities. Over time, this evolved into more formalized law enforcement structures to serve the needs of a more complex and expanding society.