Your May 4 editorial "Al Gore's Good Idea," praising Mr.  Gore's plan to require coerced drug abstinence of people released on probation, makes the common error of attributing criminality to the use of certain chemicals. This plan assumes that those with dirty urine should be jailed because they will commit robberies, burglaries and other crimes.  This supposition trifles with our most precious right, the presumption of innocence.  Some 80 million people have used illegal drugs including the majority of police officers I hired during my 18 years as police chief of two of America's largest cities. These cops, like the next president of the U.S., be he Republican or Democrat, did not commit other crimes and they grew out of their drug use.

Coerced abstinence displays a willingness to incarcerate hundreds of thousands of people because society thinks they may commit future crimes. However, as Milton Friedman, my colleague at the Hoover Institution, has pointed out, it is Prohibition, not the particular chemical substance, that leads to crime.  During the 10 years I worked as a policeman in Harlem I reached the same conclusion.  Hard-core drug users stole to buy drugs whose prices were inflated by as much as 17,000% because they were illegal.  But those addicted to other mind-altering drugs such as alcohol, Methadone, Prozac or Valium are viewed as patients, not predatory criminals.  Coerced abstinence has been labeled as "a life sentence on the installment plan."

You cite Mark Kleiman as the originator of the coerced drug abstinence plan. I have heard Prof.  Kleiman also advocate that before someone is served a beer he should have to produce a government license for the bartender indicating that he is a responsible drinker.  Presumably, violators would land in prison.

Nowhere do you mention that for roughly the first 130 years of our republic, Americans' right to life, liberty and the pursuit of happiness included the right to ingest whatever chemicals one desired.  Lest there be any doubt about this, we should remember that Thomas Jefferson, who penned those words in the Declaration of Independence, subsequently ridiculed France for imposing laws on diet and prescription drugs.  Jefferson said that a government that controls what its citizens eat and the kind of medicine they take will soon try to control what its citizens think.  Recently, the Clinton White House was embarrassed when it was disclosed that it had been secretly paying television networks, magazines and newspapers to include "correct" views on drugs for our consumption.

In 1914, congress passed the Harrison Act leading to the criminalization of drugs and our disastrous drug war.  Prior to that time, there was no black market in drugs and organized crime drug structure with its associated violence and pervasive corruption of government officials.  Drug users were not stigmatized as predatory criminals.

Drug historian David Musto, M.D., of Yale notes that narcotic use in the U.S.  had been declining for some 15 years before the federal government outlawed opium.  The decrease occurred without the government trying to eliminate drugs or jailing hundreds of thousands of Americans.  It seemed that requiring manufacturers to label what was in their products combined with public health messages was sufficient to reduce drug use.  Why does the thought of responsible citizens controlling their own lives without government coercion seem so threatening?

Joseph D.  McNamara, Police Chief of San Jose (Ret.) The Hoover Institution Stanford University, Stanford, Calif.