Supreme Court Police, US Capitol Police and the DC Metropolitan Police Department responded to the incident, which happened at about 6:30 p.m. ET.
The individual was airlifted to a local hospital after a medical helicopter landed on the plaza, and no one else was injured, according to the Supreme Court spokesperson.
“The area remains closed for further investigation, but this is not a public safety issue,” the spokesperson said.
DC police and Capitol Police did not immediately respond to requests for comment.
The incident follows a flurry of recent chaotic events in the District.