Natalie DeLeon and other D.C. marijuana advocates gather on the Capitol grounds to urge Congress to recognize the District’s laws. (Melina Mara/The Washington Post)

Ricardo Harvin addressed a small crowd of fellow marijuana activists Monday in front of the Capitol, calling on the federal government to remove marijuana from the nation’s list of most dangerous drugs and recognize that it is legal in the nation’s capital.

Preparing for a showdown with law enforcement, the D.C. resident then spoke to more than 20 U.S. Capitol Police officers who surrounded the gaggle of activists and reporters.

“Congress approved our federal law, it is federally legal [to possess] marijuana in the District of Columbia,” Harvin said, referencing the 2014 referendum in which 70 percent of D.C. voters backed a measure to legalize marijuana possession on District land. “So remember that as you come in to arrest us.”

Some lit joints minutes later, prompting Capitol Police to swarm in and arrest four people for allegedly possessing an illegal substance on federal land. Adam Eidinger, a co-founder of the advocacy group DCMJ, which spearheaded efforts to legalize marijuana in the District, was among those arrested — his second marijuana-related arrest at a demonstration in less than a week.

The advocates also urged lawmakers to remove pot from the federal list of most-dangerous drugs. (Melina Mara/The Washington Post)

Monday’s rally coincided with the Senate’s first day back in session and came days after activists distributed joints to congressional staffers on District land near the Capitol on April 20 — an annual day of celebration for marijuana supporters.

Capitol Police on Thursday ventured onto land under local jurisdiction and arrested eight activists, including Eidinger, although charges were dropped against six. Prosecutors pursued the remaining two cases under D.C. law, which allows for possession of up to two ounces of marijuana.

On Monday, activists also called on Congress to remove an amendment that Rep. Andy Harris (R-Md.) tacked onto a 2015 federal spending bill that has prohibited the city from passing local laws to legalize the sale and regulation of marijuana.

“One of the reasons we are fighting so hard to overturn this Andy Harris rider is because there’s unfinished business here in the nation’s capital,” Eidinger said. “Basically, we have legalization without commercialization.”

Natalie De Leon, 26, said that she served in the military and once relied on opioids to treat her depression, but that she felt like a zombie and nearly overdosed. De Leon, one of the four activists arrested Monday, now uses marijuana for treatment.

“I felt like a human being and who I really was,” she said. “And that’s why I fight so hard for cannabis, especially for soldiers and fellow veterans.”

Ras-Fia and other marijuana advocates rally at the Capitol on the Senate’s first day back in session. (Melina Mara/The Washington Post)

D.C. resident Dawn Lee-Carty said marijuana is the only treatment that has helped her 9-year-old epileptic daughter, who once suffered up to 60 seizures a day. She displayed the small container of cannabis oil she gives her daughter daily.

Although it is illegal to possess cannabis oil on federal land, Lee-Carty wasn’t arrested. She said it was hypocritical that police would arrest those who lit joints but not her.

“We need access,” she said. “We need a Plan B. Opiates should not be the only things we can put into our children’s bodies.”

Activists displayed marijuana — including joints, edibles and cannabis oil — in public view toward the end of the rally, although Capitol Police didn’t make arrests until activists lit joints.

Eidinger yelled “Free D.C.” as he was taken away in handcuffs.