MYSTERIES FILL BOOKSTORES

With thousands of mystery books in print, and millions of people - including President Clinton - reading them, mysteries are probably the fastest growing segment of the fiction market.

Authors like Agatha Christie and John MacDonald, Ellery Queen and Dashiell Hammett have had followings for decades. But the genre has boomed over the past four or five years.

Booksellers say that more than 100 stores across the United States now specialize in mysteries and the related suspense, police, and spy novels.

According to Mystery Writers of America Executive Director Priscilla Ridgway, the list expands to 550 when general bookstores with strong mystery sections are counted.

"The mystery has had a huge takeoff as a genre," Chuck Robinson, president of the American Booksellers Association, said during the group's recent convention in Miami Beach. "And I see some very eclectic readers."

The US president is among them. His vicarious sleuthing has added further luster, at least to authors whose books have been photographed tucked under the presidential arm - Walter Mosley, Jonathan Kellerman, and Sara Paretsky, among others.

"Mystery readers are well-educated and they read a lot - mystery fiction is not the entertainment of not-very-bright people," says Mary Helen Becker, owner of the Booked for Murder Ltd. store in the college town of Madison, Wis.

Mysteries are not really a single genre. There are the old-fashioned hard-boiled detective mysteries, the amateur sleuth story, the police procedural, the spy novel, and the "cozy," as the trade dubs stories with blunt instruments and little blood.

In the past few years, as more varied authors have begun penning these tales, the sub-categories have multiplied - the western-oriented mystery, a la Tony Hillerman, the romantic mystery, like those of Mary Higgins Clark, and the modern female detectives, created by such authors as Sue Grafton.

Both readers and authors cite two overriding reasons for the mystery's popularity - first, that it has a clear beginning, middle and end, and second, that justice prevails.

"The good guy wins and the bad guy loses," says William Caunitz, whose fifth police novel, "Cleopatra Gold," is due out soon. A former New York City cop, he says it doesn't always turn out that way in real life.