D.C. police officials declined to comment yesterday on an arbitrator's ruling that concluded they had improperly punished a sergeant who reported alleged irregularities in the compilation of crime statistics.

The decision by Jacob Seidenberg of the American Arbitration Association was made in a report released Wednesday in behalf of Sgt. Raymond Dyer, a 6th Police District detective who was transferred to scooter patrol following his complaints to union officials that crimes occurring in the 6th District were being reported in lesser categories--for example, downgraded from felonies to misdemeanors--to make it appear that the area had fewer serious crimes than it actually had.

Gary Hankins, chairman of the Fraternal Order of Police bargaining committee, hailed the decision, asserting that it "confirmed the union and Ray Dyer's position down the line." Hankins said that Dyer, in "reporting something that was wrong . . . became a victim of a conspiracy of attempts to repress it."

Hankins said Dyer was "very gratified" with the decision and expected to be reassigned to his former job as supervisor of the 6th District's investigative section.

Assistant Police Chief Marty Tapscott, who declined to comment in detail on the decision, said that since the controvery over crime classification arose, "minor corrections" have been made in an otherwise "sound" system.

Deputy Chief Issac Fulwood, who commands the 6th District that includes Capitol Hill, said that he had not seen the report. "Sgt. Dyer has been doing a good job in the job he's in," Fulwood said, "and if he goes back to the detective office, I expect he'll do a good job there."

Dyer's complaints were investigated by Deputy Chief Roland W. Perry, who said that some officers were told to downgrade reports, and that Dyer was transferred because of his opposition to the practice.

But Tapscott reviewed Perry's findings, conducted his own investigation and overturned Perry's recommendations. Police Chief Maurice T. Turner accepted Tapscott's recommendations. The case then went to abritration.