What does the code 10-21 mean in law enforcement communication?

The code 10-21 is used in law enforcement communication to indicate that an officer should place a telephone call. This code is part of a standardized set of 10 Codes, or ten signals, which facilitate concise and effective communication among officers. By using this code, it streamlines interactions and reduces the potential for misunderstandings, ensuring that all parties are on the same page regarding the need to communicate via phone. It's crucial for operations where rapid clarification or information exchange is necessary but not urgent enough to warrant immediate face-to-face interaction. This code helps maintain operational efficiency while adhering to protocols of professional communication in law enforcement.