A Maryland attorney who sat at the defense tables of former county executive Jack B. Johnson and his wife Leslie in their federal corruption cases has been suspended for misconduct in unrelated matters.

Roland N. Patterson Jr. is suspended for at least six months, the Maryland Court of Appeals, the state’s highest court, ruled in a 32-page decision.

The decision, issued Wednesday, almost entirely supports earlier findings by Baltimore County Circuit Court Judge Susan Souder, who presided over allegations brought against Patterson by the state Attorney Grievance Commission.

The appellate court supported Souder’s findings that Patterson violated Maryland Lawyers’ Rules of Professional Conduct regarding competence, diligence, and safekeeping of client property. The opinion also found Patterson mishandled client funds, including in one instance when the court concluded that Patterson took a retainer of $2,500 from a client but did little or no work.

Patterson, also a former prosecutor in Prince George’s County, did not return a phone message left at his Owings Mills office Thursday.

Hours after the Johnsons were arrested on federal corruption charges in November, 2010, Patterson sat near Leslie Johnson during her initial appearance in U.S. District Court in Greenbelt.

In May, Patterson sat at the defense table of Jack Johnson when he pleaded guilty to federal corruption charges. Patterson did not speak at either court appearance. Jack Johnson’s primary defense attorney is prominent Washington lawyer Billy Martin. Leslie Johnson is represented by Washington attorney Shawn M. Wright.

Leslie Johnson, 59, pleaded guilty in June to conspiracy to commit evidence and witness tampering. Jack Johnson, 62 is scheduled to be sentenced Dec. 6. Leslie Johnson is scheduled to be sentenced Oct. 13.

The Court of Appeals found that in November, 2008, Patterson closed a trust account, in which attorneys hold client funds. Two days after he closed that account, Patterson wrote a $500 check on that account, causing a negative balance, the appellate decision said.

Besides that transaction, the Court of Appeals supported Souder’s findings that Patterson “failed to keep his trust account records showing all deposits and disbursements.”

In another instance, Patterson did not adequately represent a man named Denver Moten in a landlord-tenant dispute. Moten paid Patterson a retainer of $2,500, but the attorney did little or no work on the matter, according to the opinion.

Souder found that Moten learned of the Feb. 27, 2009 trial date in his case by monitoring the court docket, and notified Patterson, who was unaware of the date. When Patterson testified before Souder regarding the Moten case, Sounder found the attorney’s testimony was not credible, according to the appellate court, which supported Souder’s findings.

In the Moten case, a judgement of $0 was entered against two defendants Moten had sued. Patterson charged Moten $600 to “execute” the judgment, which Souder and the appellate court found to be “unreasonable.”

In another case, Patterson represented a woman named Rachelle Lewis, who alleged that her son was injured while in the custody of the state Department of Juvenile Services. Lewis hired Patterson to file a civil lawsuit.

Souder found the lawsuit filed by Patterson was not competently drafted, but the appellate court disagreed, saying the drafting of the complaint itself “does not demonstrate a level of incompetence sufficient” to violate Maryland bar rules.

But the appellate court agreed with Souder that Patterson “neglected to perform any kind of services or undertake research, to collect documents to support the complaint,” which was dismissed when Patterson “failed to take any action.”

The appellate opinion says that Souder did not make any findings regarding mitigating factors, though Patterson suffers from multiple sclerosis. Patterson said his disease caused him to some degree to fail to respond to inquiries from the state bar counsel about the issues for which he is being disciplined. The appellate court ruled that Patterson established MS as a mitigating factor for one allegation, that he knowingly failed to respond to demands for information about his then alleged misconduct.

Patterson worked as an assistant state’s attorney under Jack Johnson, who served as the county’s top prosecutor from 1994 to 2002. Johnson assigned Patterson to the homicide unit. Patterson remained in the state’s attorney’s office under Glenn F. Ivey, who succeeded Johnson, for about three years, then left the office to launch a private practice.