Some of the best trained dogs of the nation's police and military canine corps will gather here Saturday for the week-long United States Police Canine Association's 13th national dog trials. More than 150 federal, state, county, city and military police jurisdictions are expected to be represented.

Police dogs and their handlers participating in the trials are winners of preliminary contests held last spring in each of the association's 14 regions. After this week's trials, there will be one superdog and nine runners-up, judged to be the best in a combination of contest categories. Sixteen other winners will be chosen in the agility, attack, search and obedience categories, and some special awards will be given. "It's like your Miss United States," an association spokeswoman said. "Just like that exactly."

The public is invited to watch the dogs compete at Duke Ellington High School, 38th Street and Reservoir Road NW, Monday, Tuesday and Wednesday from 6 a.m. to 2 p.m., and Thursday, Aug. 17, from 6 a.m. to the conclusion. On Monday and Tuesday, the competition will be in the obedience, agility, and article search categories. Wednesday, the competition will be in the attack and handler protection categories, as well as the boxes category, in which the dog is given a fixed amount of time to find a human being hiding in different boxes. On Thursday, the competition continues until the runners-up and the number one dog have been chosen.

The public is also invited to watch the competition in gunfire attacks on Wednesday from 9 a.m. to 3 p.m. and Thursday, Aug. 17, from 9 a.m. until conclusion at Guy Mason Field on Calvert Street and Wisconsin Avenue NW. There is no admission charge for any of the above events.

On Thursday, Aug. 17, the highest scoring dogs will demonstrate their training in a public show beginning at 7:30 p.m. at Washington and Lee High School in Arlington. An admission donation of $1 is required. If it rains, the show will be rescheduled for Friday, Aug. 18.