What is an official policy or custom in civil rights law?
In civil rights law, the term “official policy or custom” refers to state or government measures set in place--and accepted as official--that create a common practice of illegal treatment in violation of civil rights. In other words, "official policy or custom" means that the state or government that trampled on your civil rights was at least aware that the practice was widespread, and that it infringed upon either your immediate civil rights or those of others. "Official policy or custom" includes enactments that are officially legislated, such as acts in a state law or municipal ordinance.
In a civil rights legal case, when one party is suing another for discrimination, an official policy or custom comes into play when the act of discrimination is accepted and permitted to be carried out against more people than just the party bringing the lawsuit. For example, if a city government has a rule in place that people of a certain race are not allowed to attend weekly board meetings, a person of that race may bring a lawsuit against the government for this reason--and the issue would lie with the official policy that allowed such discrimination to take place under standard rulings.
It's worth noting that in order for a policy to be considered official for the purposes of civil rights litigation, it does not necessarily need to be in writing. With the above example, the city government does not necessarily have to have a written legislation stating that certain people are not allowed at the board meeting. It simply needs to be understood and acknowledged as an existing statute by the authorities, who are aware of the violation of civil rights taking place, for "official policy or custom" rules to apply.
If you have more questions about official policy or custom in civil rights law, contact a civil rights attorney.