Answer:
The DOJ's website explains that the courts have found a "pattern or practice" of discrimination when the evidence proves the discriminatory actions were part of the creditor's regular practice, and not just an isolated instance. This does not mean that the DOJ must prove that a defendant/creditor always discriminates. It means that the defendant/creditor has demonstrated a policy of discrimination, even if the policy is not always followed. In addition, the courts have held that the Attorney General has discretion that allows the DOJ to file a lawsuit even when a discriminatory act has occurred only once - if certain circumstances apply.