"The Commissioner takes care to impress upon the minds of his men the necessity of performing these various, difficult, and often delicate duties with ‘perfect command of temper.’ They are cautioned ‘not to use irritating language even to those offending against the law.’ They are not to interfere unnecessarily, but, when it is their duty to act, they are to do so with decision and boldness. ‘The police,’ says the order, ‘are not to use language towards persons in their custody calculated to provoke them; such conduct often creates a resistance in the prisoner, and a hostile feeling among the persons present towards the police.’ And again: ‘The more respectful and civil the police are upon all occasions, the more they will be respected and supported by the public in the proper execution of their duty.’"
Article from the Quarterly Review, ART. IV. - 1. Judicial Statistics. 1868. 2. Criminal Returns: Metropolitan Police. 3. General Regulations, Instructions and Orders, for the Government and Guidance of the Metropolitan Police Force. 1862. 4. Report of the Commissioner of Police of the Metropolis. 1870