Applicants to these programs are often older students. The emphasis of the course of study is on linking course work and program projects to current organizational settings. Areas of concentration could be, for example, in policing, courts or corrections. Individuals may or may not want to go for a doctorate. Time ranges from 1-3 years to acquire the degree.
Some people go on to a Ph.D. with a MA, others get jobs working in the system.
Recent MA graduates from a local criminal justice program got positions as a psychometrician with the MCAT Board, and as a data analyst with a large marketing research firm. The most prestigious of these programs tend to have excellent cachet and are worth pursuing if you want to work in a political context or in high level, public policy organization or the federal government. DPAs tend to be far less common than MPAs, and DPPs less common than MPPs. Time ranges from 4-7 years to complete the degree, depending on a host of program and individual factors that are too numerous to list here. You want to be sure to inquire of the graduate program directors with whom you speak what time to completion is.