Associated PressThe 20th anniversary of Sept. 11 terrorist attacks is fast approaching and victims' families are pressing the courts for answers to their lingering questions. The prosecution that accuses Saudi Arabia was complicit in the attacks took a significant step forward this year. Former Saudi officials were questioned under oath, but these depositions are still under seal and the U.S. withheld many other documents too sensitive to disclose. Families who have been trying for years to prove that the Saudi government was involved in the attacks are now frustrated by the information vacuum.