Decision-making in the Police service can be very complex. Police officers most often have to make decisions in very difficult circumstances and situations and may not have all the necessary or complete information to hand. It is also very important to note that the role that police officers play and the environment where they have to make decisions can be very complicated. Police officers and police staff are sometimes required to make decisions in circumstances where those involved deliberately mislead or try to mislead them. As a result it may not always lead to the best outcome.

Therefore to create a framework that could allow officers to base their decisions on, and allow for examination of each decision and allow for some form of standardisation in decision making the National Decision Model (NDM) was created.

At the heart of the NDM, the Code of Ethics highlighted is essential for all decision making. This gives confidence for police officers to use the NDM and reduces risk. Decision makers will be supported by their organisation where it can be shown that their decision was assessed by the NDM and the circumstances at the time, even when harm has resulted as part of the decision making process.