Each specialized unit has different requirements including the length of time in the department.  For example, to be eligible for detective, you must have three years of patrol experience, but to become a sergeant, you must have five years before taking the promotional exam. Constant hard work and dedication to the job along with a high degree of self-motivation will serve those who seek promotion. There is a civil service promotional process for ranks of sergeant through captain.  Promotion hire to the rank of captain and above is at the discretion of the Chief of Police.