"Reasonable suspicion" is the UK equivalent of what Americans call "probable cause" i.e. jargon for when the police are allowed to search you. The police have

"Reasonable suspicion" is the UK equivalent of what Americans call "probable cause" i.e. jargon for when the police are allowed to search you. The police have to conduct stops in a certain manner, because of the law that gives them the power to stop people: They are legally required to tell the person they're being detained for the purposes of a search, the purpose of the search, the grounds for the search, and the legal power used. Getting a load of jargon thrown at you about "detained" and "offensive weapon" and "Police and Criminal Evidence Act" sound a bit officious, but once they've stopped you they've got to give you the officious jargon, it's required by law. Also, while it's rare that the police will have occasion to stop and search a middle class, middle age white guy like myself, when the situation does come up, it's reasonable for them to do it thoroughly and by the book. They should treat a report of me carrying a knife the same as they'd treat a report of a black teenager in a bad neighbourhood carrying a knife.