What revolutionary idea did Sir Robert Peele advocate regarding police?

Sir Robert Peel, known as the father of modern policing, advocated for the idea that police should wear uniforms. This was significant because uniforms help establish a visible and recognizable presence of law enforcement within the community. The wearing of uniforms serves multiple purposes: it helps to create a sense of order and authority, instills public confidence in the police, and fosters a connection between the police force and the community it serves. Peel's principles emphasized that police should be an integral part of the community and that uniformed personnel would promote trust and accountability.

The other choices, while potentially relevant in various law enforcement contexts, do not align with Peel's foundational concepts of modern policing as he outlined them in his nine principles. For example, uniforms are primarily about visibility and accessibility, whereas the idea of unarmed police, secret operatives, or undercover operations diverges from Peel’s focus on community policing and the visible presence of law enforcement agents as a deterrent to crime.