McCants said he was told in October by a jail security employee that paperwork he was carrying had a stain on it that “looked wet.” McCants, in an interview, said that the stain was dry. He said he was then told that the paperwork contained residue that tested positive as synthetic marijuana.

McCants said a family member of one of his clients had given him the paperwork to pass along to the client. McCants said he should not have tried to deliver paperwork to the jail that did not originate with him. But he said he was distracted at the time by the death of a close friend.

“I made a mistake,” McCants said. “I may have been a little bit off. Dealing with grieving a friend’s death. I did nothing wrong. I built my integrity over a lifetime. My integrity stands in place.”

Defense lawyer Donna Beasley also confirmed that she has been banned from the jail, but declined to discuss the circumstance. Beasley said that she, like McCants, can meet with jailed clients via video and that her hired investigators can go into the jail to meet inmates in her absence.

The two Department of Corrections employees who said the lawyers were banned spoke on the condition of anonymity because of the ongoing investigation.

Inmates seeking illegal drugs can use the tainted paperwork in place of actual drugs. Roger Mitchell, a former D.C. medical examiner, said inmates could rip up the paperwork and either smoke it or place pieces of it under their tongues to get intoxicated. “That’s why all things coming into jail need to be looked at or tested,” he said.

The D.C. Superior Court Trial Lawyers Association has since reminded its 200 members that they should not bring materials into the jail unless the items originated with themselves, police or prosecutors.

Betty Ballester, a former head of the association, said a memo was distributed to members detailing what they can and cannot bring to clients. “We can bring in any kind of legal materials,” she said. “We are not allowed to bring in newspapers, books or personal items, such as pictures or letters from family members. Just legal documents.”

In a statement Thursday, Thomas Faust, the director of the Department of Corrections, declined to provide specifics of the investigation but praised his employees for identifying drug-tainted items brought into the jail.

“Our staff is trained and equipped with the necessary tools and techniques to detect and intercept contraband,” Faust said in a statement. “We employ a variety of strategies, including regular searches, advanced screening and detection technologies, and intelligence gathering, to ensure that contraband is identified and seized promptly.”

The office of D.C. Mayor Muriel E. Bowser (D) declined to comment on the two lawyers. After The Washington Post submitted a Freedom of Information Act request in October for details regarding the banning of the attorneys, Bowser’s Office of Legal Counsel denied an appeal in December, saying the details were “relevant to an ongoing investigation” and that releasing them “would impact the integrity of the investigation and any subsequent enforcement proceeding.”

Like many correctional facilities, the D.C. jail has grappled with how to stop prisoners from getting drugs. From 2021 to September, six inmates died of overdoses in the jail, according to the D.C. medical examiner’s office.

In 2022, a D.C. corrections officer and two other people, including an inmate, were charged with smuggling prohibited drugs into the jail. Also that year, two inmates died and another was hospitalized in apparent drug overdoses.

In July, inmate Marktwan Hargraves, 24, was found dead in his cell. According to a spokeswoman for the D.C. medical examiner, Hargraves died of the “combined toxic effects” of fentanyl, fluorofentanyl and mirtazapine.

Last week another inmate, 47-year-old Roy Tatum, was found dead in his cell. The cause of his death is pending autopsy by the medical examiner’s office.