Chief Steven Sund of the Capitol Hill police has resigned amid criticism about the lack of police preparedness for pro-Trump riots on Jan. 6 at the U.S. Capitol, above. By Friday, two Capitol Police officers had been suspended and at least 10 more were under investigation for their actions during the riot.After the Congress moved from Philadelphila to Washington at the turn of the 19th century, a single watchman was in charge of protecting the U.S. Capitol and its grounds.

An assault on a son of President John Quincy Adams inside the Rotunda in April 1828 encouraged the sixth president to push Congress to provide funds for more security.

Congress passed an act on May 2, 1828, that created the federal law enforcement agency, by then four members strong, charged with protecting “the Congress – its Members, employees, visitors, and facilities.”

In the modern era, Capitol Police killed a gunman who opened fire on a group of congressmen at a charity baseball event in 2017, and have been at the center of other high-profile incidents at the Capitol over the years.

In 1998, a gunman shot his way into the Capitol, killing two officers and injuring three civilians. Following the shooting, the officers lay in honor inside the Rotunda.

With the death of Officer Brian Sicknick following injuries sustained during last week’s melee, at least five U.S. Capitol police officers have died in the line of duty. U.S. flags are being flown at half staff on public buildings and military posts through Wednesday.

VICTOR COUTO is the Production Manager at Retro Report. Stay up to date. Subscribe to our newsletters.