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To arrest someone is to apprehend that person, sometimes forcibly, in order to bring him to answer for criminal charges, or else to prevent an imminently certain 'breach of the peace'. The term 'arrest' is morally neutral; anyone intentionally deprived of his liberty is thereby arrested, whether for good reason or bad. As a consequence, while one might argue whether or not an apprehended party was lawfully arrested, it would be very much incorrect to say (assuming an unlawful arrest) that the apprehended party was never arrested at all.

For further discussion see power of arrest, arrest procedure.