Search dogs
In search situations the police dog and handler team can help cover much larger areas quicker than just an officer. They can detect human scent quite a few hundred yards away and get into bushes and woodland much more easily. This, with the handler's skills to control the dog search area, means a handler and dog can search large areas more effectively and efficiently saving lots of police time.
They can help look for missing people, offenders and evidence too. It might be a vital piece of evidence for a case and the dog can be crucial for finding that missing piece of the jigsaw.