Given that preserving human brains for more than a century is fairly uncommon, what do you think was the motivation for preserving Guiteau's brain?

Context: James A. Garfield, the 20th president of the United States, was shot at the Baltimore and Potomac Railroad Station in Washington, D.C., at 9:30 am on Saturday, July 2, 1881. He died in Elberon, New Jersey, 79 days later on September 19, 1881. The shooting occurred less than four months into his term as president. Garfield's assassin was Charles J. Guiteau, whose motive was revenge against Garfield for an imagined political debt, and getting Chester A. Arthur elevated to president. Guiteau was convicted of Garfield's murder and executed by hanging one year after the shooting.

Part of Guiteau's preserved brain is on display at the Mütter Museum at the College of Physicians of Philadelphia. Guiteau's bones and more of his brain, along with Garfield's backbone and a few ribs, are kept at the National Museum of Health and Medicine, at the Army's Forest Glen Annex in Silver Spring, Maryland. Garfield's assassination was instrumental to the passage of the Pendleton Civil Service Reform Act on January 16, 1883. Garfield himself had called for civil service reform in his inaugural address and supported it as president in the belief that it would make government more efficient. It was passed as something of a memorial to the fallen President. Arthur lost the Republican nomination in 1884 to Blaine, who went on to lose a close election to Democrat Grover Cleveland.

Answer: One reason for preserving the brain may have been to study structural abnormalities that could have explained Guiteau's violent behavior. Alternatively, because Guiteau was well-known and infamous, his brain may have been preserved for use as a memento or as a warning to discourage presidential assassinations in the future.