Section 1752(a)(3) of Title 18 outlaws any intentional interference with ingress or egress to or from any of the buildings, grounds, or areas referred to in 18 U.S.C. § 1752(a). The government is clearly entitled to regulate crowds to preserve free ingress and egress to buildings. Similar statutes have been upheld by the Supreme Court. See Cameron v. Johnson, 390 U.S. 611 (1968); Cox v. Louisiana, 379 U.S. 536 (1965). See also Shenck v. Pro-Choice Network, 117 S.Ct. 855 (1997) at 868-869, upholding fixed buffer zones to permit ingress and egress at an abortion clinic.
[cited in JM 9-65.400]