Intentional discrimination is virtually impossible to prove in a court of law. The disparate impact standard could no longer be used to prove racial discrimination under Title VI of the Civil Rights Act. Not all laws allow for a private right of action. Instead, a person would need the government to bring a case for them. To prove disparate impact one has to show that a certain group suffered more than others because of a policy or action.
In Alexander v. Sandoval, Ms. Martha Sandoval, upper left, sued the state of Alabama because, as a state with an "English only" policy, they refused to give any driver's license tests in Spanish, thus discriminating against her on the basis of her national origin. The Supreme Court, in a 5-4 decision, decided that private individuals could only sue the state under Title VI if they could prove intentional discrimination, something a person in Ms. Sandoval's position would not be able to prove. After this case, if a person only has proof of a disparate impact, they have no private right of action in federal court, so they can only try and persuade the federal government to take their case, something that rarely happens. (Nat'l Campaign To Restore Civil Rights)