cell may have showers, toilets and sinks. Cells are locked at night with one or more correctional officers supervising. There is less supervision over the internal movements of prisoners. The perimeter is generally double fenced and regularly patrolled. Prisoners in minimum security facilities are considered to pose little physical risk to the public and are mainly non-violent "white collar criminals". Minimum security prisoners live in less-secure dormitories, which are regularly patrolled by correctional officers. As in medium security facilities, they have communal showers, toilets, and sinks. A minimum-security facility generally has a single fence that is watched, but not patrolled, by armed guards. At facilities in very remote and rural areas, there may be no fence at all. Prisoners may often work on community projects, such as roadside litter cleanup with the state department of transportation or wilderness conservation. Many minimum security facilities are small camps located in or near military bases, larger prisons (outside the security perimeter) or other government institutions to provide a convenient supply of convict labor to the institution. Many states allow persons in minimum-security facilities access to the Internet. Correspondence Inmates who maintain contact with family and friends in the outside world are less likely to be convicted of further crimes and usually have an easier reintegration period back into society. Inmates benefit from corresponding with friends and family members, especially when in-person visits are infrequent. However, guidelines exist as to what constitutes acceptable mail, and these policies are strictly enforced. Mail sent to inmates in violation of prison policies can result in sanctions such as loss of imprisonment time reduced for good behavior. Most Department of Corrections websites provide detailed information regarding mail policies. These rules can even vary within a single prison depending on which part of the prison an inmate is housed. For example, death row and maximum security inmates are usually under stricter mail guidelines for security reasons. There have been several notable challenges to prison corresponding services. The Missouri Department of Corrections (DOC) stated that effective June 1, 2007, inmates would be prohibited from using pen pal websites, citing concerns that inmates were using them to solicit money and defraud the public. Service providers such as WriteAPrisoner.com, together with the ACLU, planned to challenge the ban in Federal Court. Similar bans on an inmate's rights or a website's right to post such information has been ruled unconstitutional in other courts,