Although statistics indicate that drunk drivers are responsible for about 50 percent of all motor vehicle accidents, the justice system must balance the need for public safety against the fourth amendment rights of motorists. In the interest of public safety, law enforcement officials have set up sobriety checkpoints to apprehend drunk drivers. Sobriety checkpoints operate on an arbitrary basis, i.e., every fifth or sixth vehicle is stopped. Despite the lack of probable cause to stop each vehicle, drivers are questioned to determine if they have been drinking. This has generated numerous lawsuits challenging the constitutionality of the checkpoints under the fourth amendment. The U.S. Supreme Court has upheld only those checkpoints which contain safeguards to protect the rights of motorists and which result in only a minimal intrusion. In general, therefore, case law suggests that sobriety checkpoints operated according to extremely strict guidelines and supervision will be upheld as constitutional under the fourth amendment. Checkpoints set up or operated by field officers acting entirely at their own discretion will likely be invalidated. Appendixes contain sobriety checkpoint operating policies and procedures of the Los Angeles Police Department. 182 footnotes