Laws for posting a piece of real estate with no-trespassing signs vary from state to state. Strict compliance with local trespassing laws is required if a landowner wishes to be able to pursue prosecution against unwanted trespassers, as well as to protect herself from liability if those trespassers are injured on the property. In many states, open or forested land is open to hunting and other uses by the general public, unless it is clearly posted, in accordance with law.
Criminal trespass is the presence of a person on the land of another where they are not permitted. Trespass on the 'curtilege'--a residence and the yard immediately surrounding it--can often be criminally charged without no-trespass signs or without verbal or written warnings, because the location is clearly occupied. Trespass on fields, forests, or other unoccupied land is not as clear. Often the law considers property to be open for reasonable public uses--walking, nature photography, hunting and fishing--unless legal warning has been given that the property is closed to all but the owner and her invited guests.
To lawfully close her property, a landowner must post it in accordance with laws currently in effect in that jurisdiction. Posting laws may be found in state statute books. Town clerks and persons who sell hunting and fishing licenses often have copies of the state's posting laws. Generic information about posting published by national organizations will not necessarily meet the legal standards of a particular jurisdiction; carefully read the state posting statute and any local posting ordinances to ensure no-trespass signs are lawfully posted.
Size and Appearance
Some posting laws mandate specific sign sizes and colors, while others merely require that signs be obvious and readable. The Montana unlawful trespass statute, Mont. Code Ann. Section 45-6-201, for example, requires no-trespassing signs be "conspicuous" and placed on a "post, structure, or natural object...with not less than 50 square inches of fluorescent orange paint...". Vermont requirements for no-trespassing signs are found in the fish and game statutes, Title 10 VSA Appendix Section 14, and require signs to be at least 11.5 inches wide and 8 inches high, with lettering and background of contrasting colors.
Location and Quantity
Laws regarding posting usually require no-trespassing signs to be erected along the boundaries of the property at certain intervals. The Vermont posting statute, for example, 10 VSA Section 5201, requires that signs be set "upon or near the boundaries of lands to be affected with notices at each corner and not over 400 feet apart...". California Penal Code Section 602.8 requires no trespassing signs to be posted "at intervals not less than three to the mile along all exterior boundaries and at all roads and trails entering the lands...".
Many states require persons who are posting their lands to register or record that posting with their town clerk or land records office annually. In Vermont, the landowner must record a posting form each year in the town land records, and pay the town clerk a $5 fee for the recording. In jurisdictions which require the no-trespassing signs to be signed and dated, landowners will have to physically re-post new signs each year.
Effects and Misconceptions
Uninvited persons on lawfully posted lands can be prosecuted for trespassing. Landowners with properly posted lands also help protect themselves from liability if an uninvited person is injured on their property. No-trespassing signs will not, however, keep all governmental inspectors off the property. Posting diminishes lawful access for private corporate inspectors and for governmental officials engaged in civil investigations like zoning compliance, but many law enforcement or military activities will not be required to respect no-trespassing signs.
Cultural perspectives regarding no-trespassing signs vary in different parts of the country. In some regions, hunting or wild-foods gathering is considered the birthright of all residents of the area, and posting is considered antithetical to local culture. In other regions, profound respect for property boundaries is the prevailing sentiment. Legal standards reflect these differences: The laws of some jurisdictions make it easy for landowners to post their property; other jurisdictions require the landowner to pay fees and to strictly comply with onerous posting requirements.