THE STATE'S hearing examiner is right in his judgment on the Montgomery County school appeals. His findings are unusual in the sense that the Maryland State Board of Education has always shown great reluctance to get involved in local disputes over closing schools and changing attendance boundaries. But in these cases, the examiner, Mitchell J. Cooper, joins most other people who have examined the decisions made by the Montgomery school board last fall in concluding that the board violated its own principles.

The county school board had voted to close the Rosemary Hills Elementary School, which was paired with Chevy Chase. Rosemary Hills serves a neighborhood with many black families, and the board argued that dispersing the black children through several other schools would eliminate the present concentration at the one nearest their homes. The Rosemary Hills School illustrates the point that racial concentration should not be the only consideration in school policy. As Mr. Mitchell suggests, low ratios of black children in the classroom become offensive if they are achieved by placing special burdens, and disproportionately long trips, on those children.

The Montgomery school board's defense of its dispersal policy at Rosemary Hills would have enjoyed more credence if it had not done the opposite at Montgomery Blair High School. There it amended the boundaries to turn the Beltway into a sort of moat, separating the older neighborhoods of Silver Spring from the subdivisions to the north. The effect would be to increase the proportion of black, Hispanic and Asian children at Blair. The new boundaries would also imply a sharply diminished enrollment at the school, suggesting that it, too, would presently become a candidate for closing.

The examiner's findings have been presented to the state board, which has the authority to overrule the county. It would be greatly to the county board's credit if it took this impartial and informed opinion as an occasion to reconsider its earlier decisions. But that doesn't seem very likely.

These school cases are an unhappy exception to Montgomery's tradition of excellence in government and fairness in dealing with its citizens. If there is any community in the United States well equipped to set a high standard, it is Montgomery. But if its county school board cannot bring itself to remedy its errors, the state board--as the examiner concludes--will have a duty to intervene.