Most of the charges in a $1.2 million suit filed by the former owner of nine townhouses on Seaton Street NW against former supporters of tenants there were dismissed last week by D.C. Superior Court Judge William C. Pryor.

A charge against Johnny Barnes, an attorney and legislative assistant to Del. Walter Fauntroy, is still pending.

In the suit, filed in July 1977, landlord James Ruppert named Barnes, the Adams-Morgan Organization (AMO), and Marie Nahikian, a tenant member of the D.C. Rental Accommodations Commission, as defendants, and sought $400,000 in damages from each of them.

The suit involved "a multiple-count complaint, allegations of interference with a contractual relationship, champerty and maintenance, and violation of the plaintiff's civil rights," Pryor said in his order last week.

The charge of "maintenance" against Barnes, which is still pending, stems from Ruppert's assertion that "defendant Barnes, an attorney, assisted by others, filed suit against a landlord (Ruppert) on behalf of a tenant, who was not his client, with knowledge that the action was groundless," Pryor said. The judge defined maintenance, as it is used in this suit, as "the act of stirring up litigation and strife" for "the gain of profit."

When Ruppert sold several houses on Seaton Street to Centre properties of Bethesda in 1976, tenants filed suit against the landlord, charging that they were denied their right to make the first offer to purchase the houses. The suit was settled out of court in May 1977, and nine families were able to purchase the homes they had been renting. Barnes represented the tenants in their suit but did not charge them for his services, according to another attorney who also represented the tenants.

In his suit, Ruppert accused Barnes, Nahikian and the Adams-Morgan Organization of conspiring to persuade Katherine Green, a Seaton Street tenant, to falsely sue him.At the time he filed the suit last year, Ruppert said Green's home was not among the houses sold to Centre Properties.Barnes replied at the time that court action on Green's behalf was dropped when it was learned that her house had not been sold.

Champerty, one of the charges against all the defendants that was dismissed, is common-law terminology for an offense that "has been viewed in the law as a practise where one brought litigation with a purpose to share in the proceeds if litigation proved successful," Pryor said.

No date has been set for action on the charge against Barnes. Barnes' attorney declined comment on the case and Barnes could not be reached.