If the officer determines based on his/her observations during the tests that the driver is impaired and has probable cause to arrest the person for suspicion of driving under the influence, the arrestee will be asked to take an alcohol breath test or a blood test. It is important to note that the driver cannot "pass" or "fail" a field sobriety test as they are not "pass-or-fail", they are only meant to aid the officer in determining if a suspect is impaired based on observations of the subject's performance on these tests. There are various guidelines are presented by the various states (US) as well as International rules for these type Sobriety Checkpoints or DUI. For example, in the U.S. Field sobriety tests (FSTs or SFSTs) are voluntary. While the Fourth Amendment (1791) protects people against unreasonable searches and seizures of either self or property by government officials, the use by police of sobriety checkpoints in the US is not prohibited by the Fourth Amendment. Some states such as Washington state have determined that sobriety checkpoints are unconstitutional under state law. Law enforcement often posts or announces in advance that these checkpoints will occur and at what location. Law enforcement agencies often post a sign during the weekdays when it is only seen by local residents and not by those attending a special event or those that only travel in that area of the city during the weekend to patronize local bars and clubs. These announcements are also sometimes printed in newspapers. Numerous websites host a database of checkpoints that are to occur based on information found in newspapers, the Internet and tips from visitors of such sites. In the 2010s, there are smartphone apps that allow users to report sobriety checkpoints, show them on a map and use the device's GPS to alert other drivers when a sobriety checkpoint is nearby. Sobriety checkpoints regularly catch much more than just drunk drivers, as those selected to participate in the checkpoint are asked to provide their driver's licenses. As part of the standard protocol, the person's name and identifying information is run through the National Crime Information Center database, or NCIC, for wants and warrants. If the driver has an outstanding warrant, he/she will likely be arrested. If he/she was driving without a valid license, he/she will likely be cited for driving with a suspended or revoked license. The identity checks