Former U.S. Vice presidential candidate and Alaska Governor Sarah Palin (R) greets some of the thousands of motorcycle enthusiasts and military veterans participating in 'Rolling Thunder' rally May 29, 2011 in Arlington, Virginia. Although not an official guest, former U.S. Vice presidential candidate and Alaska governor Sarah Palin is expected to participate in today's motorcycle parade from the Pentagon to the National Mall.

Images created with Post-it notes are seen in the windows of offices at 75 Varick Street in lower Manhattan, New York, U.S., May 18, 2016, where advertising agencies and other companies have started what is being called a “Post-it note art war” with employees creating colorful images in their windows with Post-it notes. (Photo by Mike Segar/Reuters)

A competitor laughs while taking part in the office chair race ISU-1 Grand Prix in Tainan, southern Taiwan April 24, 2016. It was the first time such a race was held in Tainan, as part of the “ISU-1 GP” (Grand Prix) that began in Japan in 2010, according to businesses on Jhengsing Street and Haian Road in the city's West Central District and the city's Tourism Bureau, which organized the event. The fastest rider only took six seconds to complete the 30-meter race. (Photo by Tyrone Siu/Reuters)

James Brady and a police officer are seen lying on the ground after being shot while the suspect John Hinckley Jr. is apprehended,at right, moments after the attempted assassination of President Ronald Reagan, Washington, DC, March 30, 1981. (Photo by Dirck Halstead/Getty Images)

Staff members for U.S. Sen. Jeanne Shaheen (D-NH) push a stuffed moose into their office on Capitol Hill on June 11, 2024 in Washington, DC. A stuffed moose named “Marty the Moose” and a stuffed bear named “Kodak the Bear” will be on display in Shaheen's office as part of the thirteenth annual Experience New Hampshire event. (Photo by Andrew Harnik/Getty Images)

White House Press Secretary James Brady and District of Columbia police officer Thomas Delahanty lie wounded on the ground after John Hinckley Jr. fired six shots at President Reagan outside the Washington Hilton Hotel in Washington, DC, on March 30, 1981. (Photo by Courtesy Reagan Library via Reuters)

A mob attacks a female police officer accused of shooting a protester in the Buterere neighborhood of Bujumbura, Burundi, May 12, 2015. Protesters opposed to the president's decision to run for a third term chased, beat and stoned the woman, who was later handed back to the police. (Photo by Goran Tomasevic/Reuters)

Nepalese police officers worship a dog during the dog festival as part of Tihar celebrations, also called Diwali, at the Central Police Dog Training School in Kathmandu, Nepal October 29, 2016. Dogs are worshipped to acknowledge their role in providing security during Tihar festival, one of the most important Hindu festivals that is also dedicated to the worship of the goddess of wealth Laxmi. (Photo by Navesh Chitrakar/Reuters)