The Tower is sacred to several Plains tribes, including the Lakota, Cheyenne and Kiowa. Because of this, many Native American leaders objected to climbers ascending the monument, considering this to be a desecration. The climbers argued that they had a right to climb the Tower, since it is on federal land. A compromise was eventually reached with a voluntary climbing ban during the month of June when the tribes are conducting ceremonies around the monument. Climbers are asked, but not required, to stay off the Tower in June. According to the PBS documentary "In the Light of Reverence", approximately 85% of climbers honor the ban and voluntarily choose not to climb the Tower during the month of June. However, several climbers along with the Mountain States Legal Foundation sued the Park Service, claiming an inappropriate government entanglement with religion.