Mayoral candidate John Ray yesterday attacked Mayor Marion Barry's handling of layoffs of city workers during the city's 1980 financial crisis, citing a July 16 decision by the federal Merit Systems Protection Board ordering the reinstatement of six city employes who the board said were improperly dismissed.

"Once again this demonstrates how amateurish this government is at handling the tools of government," said Ray in a press conference in his council chambers.

The merit board, handling the employes' appeals under a contract with the city government, ordered the six workers reinstated with back pay. It found that in reducing the work force to meet a threatened budget shortfall, the city improperly classified employes in three separate groups and prevented them from switching categories to compete for all available jobs in the government.

Although the board's decision involved only six of the 688 city and school board employes eventually laid off, Ray said there are 115 similar cases pending before the panel. He estimated the cost of giving back pay to the six employes at about $300,000, and said if the other cases are decided in the same way, the city could face a back pay bill of nearly $3 million.

After Ray's press conference Barry said he was not aware of the decision made last month by the board.

"I don't know about this case specifically," Barry said at his campaign headquarters, "but we'll have to see what the next step is. The city has some rights, too."

Judith W. Rogers, the city's corporation counsel, said her office is reviewing the board's decision to determine whether it should be appealed. She said the six employes, who were laid off June 12, 1980, from the D.C. Office of Personnel Management's training division, were not yet back in their jobs.

The training division of the department has been eliminated but the board's order specifies that the employes are to be reinstated in their jobs within 20 days of the decison--by today.

Rogers disputed Ray's claim that the remaining cases before the board were similar to the six already decided. She said some of the other cases involve questions of whether the dismissed employes filed their appeals "in a timely fashion," and that some involve departments in which layoffs were handled in a manner that would be appropriate under the board's July 16 ruling.

"The decision says that within the same department people cannot be treated differently," said Rogers. "In some departments everyone was treated the same way."

Ray said he had questioned Barry on whether the layoffs were being conducted legally at the time they were being done. Ray said he suggested the city impose a hiring freeze and reduce its employes by attrition. Yesterday he said he still believes the city should have a hiring freeze because he thinks the government is still overspending.