Appeal from the United States District Court for the Eastern District of Washington Robert H. Whaley, Senior District Judge, Presiding D.C. No. CR 08-00018-RHW-1.
The opinion of the court was delivered by: Graber, Circuit Judge
Submitted July 16, 2010*fn1 Seattle, Washington
Before: Susan P. Graber and Richard A. Paez, Circuit Judges, and Larry A. Burns,*fn2 District Judge.
Defendant James A. Bohn did not wear a helmet while riding his motorcycle on a federal road located in the Lake Che- lan National Recreational Area, and he disobeyed a National Park Service ("NPS") ranger's orders to stop and to identify himself. Defendant challenges an NPS traffic regulation that adopts the substantive prohibitions of state law, including the requirement that motorcyclists wear helmets. We hold that, pursuant to its powers under the Property Clause, the federal government may enforce that regulation on land over which it has merely proprietary jurisdiction. Finding no merit in Defendant's arguments on this or any other issue, we affirm.
FACTUAL AND PROCEDURAL HISTORY
There is a road in the Stehekin Valley of Washington state. The Stehekin Valley Road originated as a county road, but Chelan County transferred its interest in the road to the federal government in 1970.*fn3 The Stehekin Valley Road is located within the Lake Chelan National Recreational Area, which the NPS administers as part of the North Cascades National Park Service Complex.
On August 24, 2007, Defendant and a companion passed an NPS ranger on the Stehekin Valley Road. The ranger saw that Defendant and his companion were riding motorcycles and that neither one of them was wearing a helmet. The uniformed ranger, who was in a marked NPS vehicle, motioned for the motorcyclists to stop. As they continued past him, he also verbally ordered them to stop. Defendant acknowledged the order, but did not stop. The ranger then drove after the motor-cyclists, honking his horn at them and motioning repeatedly for them to pull over. Defendant's companion pulled over and stopped. Defendant did not. The ranger followed Defendant.
Defendant eventually stopped at a building farther down the road. The ranger stopped also and asked Defendant for his name. Defendant provided only his first name and refused to give his last name. However, the ranger deduced Defendant's last name from the first name and from Defendant's local reputation. Defendant left on his motorcycle shortly thereafter.
The ranger cited Defendant for failure to wear a helmet, in violation of 36 C.F.R. § 4.2(b), and for refusing to obey a lawful order, in violation of 36 C.F.R. § 2.32(a)(2). At trial, Defendant subpoenaed the Chelan County sheriff to testify as a defense witness. The sheriff did not appear to testify, and Defendant accused the prosecutor of telling the sheriff not to come to testify. But the magistrate judge found that the sheriff voluntarily failed to appear. After a bench trial, the magistrate judge found Defendant guilty of the violations and entered judgment against him. On appeal, the district court affirmed the judgments of conviction. Defendant timely appeals.
 Congress authorized the NPS to regulate the use of the Federal areas known as national parks, . . . to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unim-paired for the enjoyment of future generations.
16 U.S.C. § 1. The Secretary of the Interior has the authority to issue "such rules and regulations as he may deem necessary or proper for the use and management of the parks." Id. § 3.
 Pursuant to that congressional grant of rule-making authority, the NPS issued 36 C.F.R. ...