Circle Officer

A circle officer (CO) is a police officer of the rank of deputy superintendent of police (DSP) or assistant commissioner of police (ACP) heading an independent police sub-division in the states of Rajasthan, Uttarakhand and Uttar Pradesh in India. In other states the officer of the same rank is also designated simply as deputy superintendent of police or In metropolitan cities or cities where the police force is headed by a police commissioner, the officer of the same rank of deputy superintendent of police is designated as or assistant commissioner of police.

Recruitment to this rank is made either directly or by promotion. The State Public Service Commissions conduct the State Civil Services Examination periodically to recruit police officers directly to this rank. Another manner of recruitment is by recruiting the officers who have risen through the junior ranks to the rank of the circle officer or deputy superintendent of police or assistant commissioner of police.

...
Wikipedia