Because slightly over half of law enforcement volunteers are 55 years old or over, AARP has conducted studies of volunteers in police support roles such as crime analysis, clerical work, crime prevention, victim assistance, and communication. Reflecting opposition to the use of volunteers by police unions, the AARP study found that about 25 percent of volunteers experience some rejection by sworn officers concerned over job security, loss of overtime pay, personal safety, and police professionalism. Of agencies surveyed, 39 percent cited improved service, 30 percent cited crime prevention, 12 percent cited increased public support, and only 1 percent cited budget constraints as the chief rationale for using volunteers. While some agencies expressed concerns over liability and confidentiality, these were overcome through training, rules and guidelines, access control, and background checks. Over half of the agencies said volunteers cost the department nothing, and only three spent more than $200 per year per volunteer, with the average expense being $24.12. A majority of agencies found the volunteers reliable, motivated, adaptable, and productive. Reservist, auxilliary, and volunteer programs have encompassed a broad spectrum of jobs in such areas as parking enforcement, neighborhood watch, an elderly check-in service, crisis intervention, victim counseling, and police ministations.