The Maryland Racing Commission stirred up a local controversy and attracted national attention when it voted to ban the use of Lasix in Grade I stakes.

Purists hailed the move, which would require horses in the Preakness and the Washington, D.C. International to run on nothing but hay, oats and water. Opponents pointed out the logical inconsistencies of the commission's ruling.

A letter from the managements of the state's two tracks, drafted by Pimlico General Manager Chick Lang, declared: "The rationale for permitting (Lasix) is that it is in the best interest of racing to allow horses with respiratory ailments to receive medication. . . . . We believe there is no rational basis for treating the Preakness and the International any differently from the other races run in the state of Maryland."

That's a good argument. But there's a good answer to it, based disturbing byproducts of California's experience with legal medication.

California adopted a liberal medication program in 1969 and it has worked so well and been so widely accepted that the subject generates no controversy here as it invariably does in the East. It is hard to argue with success; the era of medication in California has coincided with tremendous growth in the quality of racing.

California racing once was distinctly inferior to the competition in New York. But the stakes horses in the West have achieved parity with their counterparts in the East. That has been clear since 1982, when California horses won the Kentucky Derby, the Kentucky Oaks and all three legs of New York's fall championship series.

Top racehorses make top stallions, and so the recent generations of California-based horses should have begun to put their stamp on the future of the breed. But it hasn't happened. In fact, the performance of California horses at stud has been strikingly dismal.

In the ranking of America's top stallions compiled by The Blood Horse, not a single California-based racehorse appears in the top 30. The best horses who have campaigned here in the medication era have been conspicuous failures at stud.

Affirmed has been a terrible disappointment as a sire. So has Spectacular Bid, who campaigned here as a 4-year-old. Crystal Water, one of the best California horses of the 1970s, has been dismal at stud. So has the brilliantly fast Triple Bend.

The years and years of top-quality California racing have not produced a single top-class stallion; the state's breeding industry is still woeful.

There may be a number of possible explanations for this phenomenon, but I would offer this one: When horses who require medication win major stakes, they get good opportunities when they go to stud, but they are likely to beget offspring who are similarly infirm or dependent on drugs. Legalized medication is distorting the selection process that contributes to the "improvement of the breed."

There are practical reasons for allowing drugs such as Lasix and Butazolidin in run-of-the-mill races; we need to keep horses healthy enough to keep running and put on sport's daily show. But it makes no sense to help horses with physical problems so they can win championship races over rivals who don't need drugs. California and the rest of the states that allow medication should follow Maryland's enlightened example and ban drugs from Grade I stakes.