$11.756 million cost of the new wing. Work by the contractor, Robert E. McKee of Dallas, Texas, was scheduled to be complete by October 1968. Strikes, bad weather, delivery problems for materials and design changes pushed the proposed completion to July 1969. The Hall of Justice was finally dedicated on December 13, 1969. Landmark designation In recognition of its exceptional design the Marin County Civic Center main building was listed on the National Register of Historic Places on July 17, 1991 and was designated a National Historic Landmark the same day. The designation as a National Historic Landmark came thirty years after completion of the first construction phase, compared with the more usual 50-year term before a site is considered eligible for the National Register. It is also a California Historical Landmark, Number 999. In 2015 and 2016, it and other Wright buildings were considered for designation as a UNESCO World Heritage Site. In 2016, the nomination to the World Heritage List was not approved by the UNESCO World Heritage Committee. A revised 2018 proposal removed the Marin County Civic Center from the list of nominated buildings. That list of Wright buildings was approved in 2019. Attacks In August 1970 the Civic Center, which houses the Marin County Superior Court, was the scene of an attempted jailbreak led by Jonathan Jackson, the brother of Black Panther militant George Jackson, demanding the release of the so-called "Soledad Brothers". Jackson released several prisoners in the courtroom and the group took a number of hostages, including the presiding judge, Harold Haley. While they were attempting to escape, four people, including Judge Haley and Jonathan Jackson, were killed. The story, which featured dramatic photographs, was carried in newspapers nationally. Black Panther activist Angela Davis was eventually tied to the case, prompting her to go on the run before being caught and ultimately acquitted on charges of supplying firearms to Jonathan Jackson. Aaron Green designed a landscaped area near the Hall of Justice as a memorial to Judge Haley. Later that same year, in October 1970, the Weather Underground detonated a bomb at the Courthouse in retaliation. In popular culture The Marin County Civic Center was a filming location for director George Lucas's first feature-length film, THX 1138 (1971). Lucas would later use elements of the Civic Center's design as inspiration for structures on Naboo in the Star Wars prequel trilogy. The building also inspired