Which principle did Horton v California primarily focus on regarding police procedures?

Horton v. California primarily focused on the procedures for executing search warrants. In this case, the Supreme Court clarified important aspects of the Fourth Amendment, particularly surrounding the "plain view" doctrine. The ruling established that if police are lawfully in a position to view evidence, they may seize that evidence without a warrant if it is immediately apparent that it is contraband or evidence of a crime. This case emphasized the procedural safeguards necessary in the execution of search warrants, ensuring that law enforcement officers adhere to constitutional protections while also allowing them the flexibility to act on unintended discoveries made during lawful searches.

While the other choices pertain to important aspects of law enforcement practice, they do not encapsulate the central focus of Horton v. California. The ruling does not directly address the legal aspects of detaining individuals, conducting investigations, or the justification for using force, reinforcing why the correct focus is specifically on search warrant procedures.