Whilst it must be admitted that the authorities on the subject of how far and under what circumstances a municipal corporation is liable for the acts of its agents, are not uniform *469or satisfactory, yet we think it will be found that the current of the authorities is almost- uniform that it is not liable for a trespass or assault by a police officer. If he has authority to arrest, then nobody is liable,’ if he has not, then he is acting wilfully on his own responsibility, and in such cases the rule of respondeat superior does not apply. But the authorities place this kind of a servant on special grounds. He is a peace officer; his duties do not lie in the line of the special private duties or fights of the corporation, but they are duties connected with the public peace in which the state is interested, and in a very wide sense he is a state officer; many of his duties are duties connected with the prevention and punishment of crime: See Dillon on Municipal Corporations, sections 33, 34, 149, 773; and as to such officers, the ruling is almost- universal that the corporation, though it appoints them, is not liable for torts committed by them : 1 Allen, 172, 417; 31 Maryland, 462; 31 Alabama, 469; 9 La. An., 461; 17 Gratt, 375. For these reasons we affirm the judgment.

Judgment affirmed.