Police security along tomorrow's parade route for the Ku Klux Klan will close off parts of the Mall, the Capitol grounds and Constitution Avenue to tourists and motorists, according to plans released yesterday by local and federal police.

D.C., U.S. Park and Capitol police, who have overlapping jurisdictions along the parade route, will put an estimated 3,000 officers on the streets for the Klan's safety during the demonstration.

Concern about the possibility of a violent confrontation between the estimated 100 Christian Knights of the Ku Klux Klan and an unknown number of counter-demonstrators headed by the All Peoples Congress has led to the unusually tight security. The Klan group has a permit to begin gathering at the Washington Monument grounds at noon, march along Constitution Avenue NW and then rally on the east steps of the Capitol.

The last time such strict measures were taken was when a different Klan group held a rally in Lafayette Square in 1982. That event ended in a melee in downtown Washington, with 12 officers injured and a number of businesses looted.

Yesterday, Hillel Cohen, an organizer for All Peoples Congress, said his and an affiliated group have received permits to demonstrate against the Klan at three places along the parade route, but they would not make use of them.

"They wanted us to be out of the sight and sound of the Klan," he said. "They want us to be invisible. If the Klan marches, we will follow them every step of the way."

Cohen said the goal of his organization is to stop the Klan from marching, and that the demonstrators will confront the Klan near 15th and Constitution Avenue NW, the beginning of the parade route. He said his group expects to discourage the Klan from marching by "bringing out enough protesters that the Klan will be afraid to march."

Last night, Klan leader Virgil Griffin said the members will march as scheduled and will be peaceful and orderly.

Sam Jordan, deputy director of the Office of Emergency Preparedness, who is coordinating the event, said yesterday that he believes the march will be orderly because there will be enough police officers on hand.

At a forum Thursday night sponsored by a protest group called Refuse and Resist, four speakers debated whether the Klan has a right to march. Fliers for the debate, attended by about 50 people, said, "Some say, 'Freedom of speech no matter what!' and others say, 'Not to promote genocide!' "

Refuse and Resist national council member C. Clark Kissinger and Jesse McDade, a Morgan State University professor, argued that giving the Klan a permit to march amounts to a conspiracy by the federal government to promote white supremacy.

Arthur Spitzer, legal director of the Washington regional office of the American Civil Liberties Union, suggested that the golden rule of doing unto others as you would have them do unto you is useful. Diane Flanagan-Montgomery, acting president of the Urban League, said the Klan is merely exercising a right that belongs to all Americans.

The Anti-Defamation League of B'Nai B'rith said yesterday the counter-demonstrators "have the potential for violence, and often place law enforcement officers in the difficult position of being caught in the middle between protecting individuals as they exercise their First Amendment rights and maintaining order."