A year ago, I was uncertain about the Lasix issue. Since then, I've studied the science, notably a South African study financed but now disavowed by the Jockey Club that shows (a) that some 80 percent of horses have at least internal bleeding when they race and (b) that Lasix helps eliminate or reduce the level of bleeding. The more I learned, the more I'm convinced that Lasix is the most humane solution to a persistent problem. In fact, I've become so convinced that I was deeply involved in drafting N.Y.T.H.A.'s response to the state.

Horses bleed. While only a few (1 percent to 5 percent) bleed visibly through the nose or mouth, many more have internal bleeding in the lungs and trachea. And that internal bleeding causes cumulative damage. The more horses bleed, the more likely they are to bleed in the future. At the extremes, severe bleeding can cause a horse to die on the racetrack.

Lasix works. All the studies show that a modest dose of Lasix greatly reduces the incidence and severity of bleeding. Since Lasix was introduced in New York in 1995, severe, visible bleeding has been reduced by 76 percent. Whatever the cause of the far-too-many fatalities at Aqueduct this winter, it wasn't Lasix. As Hall of Fame jockey Jerry Bailey said on this year's Kentucky Derby telecast, "I've never had a horse break down under me because of Lasix."

Unlike (now-barred) steroids and other illegal drugs, Lasix doesn't enable a horse to perform beyond its natural ability, only to be more likely to reach that ability. And whatever the situation may have been years ago, Lasix no longer interferes with testing for other illegal drugs. New York now tests racehorses for some 900 illegal substances, and leading equine toxicologists unanimously agree that Lasix doesn't mask any of those drugs.

If Lasix is barred, trainers will revert to the cruel and illegal methods used in the past to limit bleeding. They'll withhold water, and perhaps food, from horses for 24 hours or more before a race. They'll use illegal, and less effective, drugs like "Kentucky Red" or tranexamic acid – both of which have been detected in "Lasix-free" jurisdictions. Or they'll use trainer Woody Stephens's old trick of giving his grooms red towels to wipe off the blood before anyone noticed.

New York's horsemen support getting tough on the drug cheaters. We've proposed to the State Racing Board that they tighten limits on painkillers, corticosteroids and clenbuterol, and that they make permanent the current arrangements under which Lasix is administered in specified dosages by veterinarians who work for the state or the racetrack, not the trainers. But we don't support a Lasix ban that would inflict unnecessary pain on the horses that we love and that would serve no purpose other than the ego gratification of a few of the 1 percent.

This article does not necessarily represent the views of either N.Y.T.H.A. or B.E.S.T.

Steve Zorn, a lawyer and law professor in New York, is the racing manager of Castle Village Farm thoroughbred partnerships and a director of the New York Thoroughbred Horsemen's Association and the Backstretch Employees Service Team. He writes the Business of Racing blog.