The U.S. Supreme Court, in a key immigration ruling, struck down three major provisions of Arizona’s law (Senate bill 1070) targeting illegal immigrants. However, one key part of the Arizona law was deemed constitutional—paving the way for it to go into effect.

The court ruled that the state provision requiring police to check the immigration status of someone they suspect is in the country illegally is constitutional.  However, the justices did state that the provision could be subject to additional legal challenges.

The justices also stated that the police have limited authority. They must check with federal immigration agents before deciding to hold the suspects due to the federal governments ultimate authority on immigration. Thus, Arizona’s police can notify federal agents if they have a suspect in custody, but they cannot keep them in a county jail on state charges. By taking the power out of the officers’ hands to arrest people on minor immigration charges, it has greatly limited the effectiveness of this provision.

The court struck down the following three major provisions: requiring all immigrants to obtain or carry immigration registration papers, making it a state criminal offense for an illegal immigrant to seek work or hold a job and allowing police to arrest suspected illegal immigrants without warrants.

Chief Justice John Roberts and Justices Stephen Breyer, Ruth Bader Ginsburg and Sonia Sotomayor joined all of Kennedy’s opinion. Justices Antonin Scalia and Clarence Thomas would have allowed all the challenged provisions to take effect. Justice Samuel Alito would have allowed police to arrest undocumented immigrants who seek work, and also make arrests without warrants.

Sixteen states had signed an amicus brief in support of the Arizona law—which included Nebraska.