U.S. Attorney Stanley S. Harris said yesterday that drug traffic, which he called "a cancer in the community," and the violent crime it breeds will be the major law enforcement priorities during his tenure as the city's top prosecutor.

"The community . . . is just fed up with violent crime and tired of being captives to the very small number of people who have no respect for the person or the property of others," said Harris, who was sworn in as U.S. attorney two weeks ago.

During a luncheon meeting with editors and reporters of The Washington Post, Harris said he will work through his office to improve the efficiency of the court system here. He said he would support measures to limit sentences on minor crimes in order to avoid long and costly jury trials, and he would also favor changes in bail law to make it easier to detain accused criminals who are believed to be dangerous to the community.

Harris, a judge on the D.C. Court of Appeals for 10 years before he was nominated to the prosecutor's job by President Reagan, said he sees a wide range of problems associated with crime control--from computer breakdowns to massive caseloads--as well as what he views as more subtle and unexplained origins of criminal behavior.

"It's pretty hard to think there may not be some genetic predisposition," Harris said when asked if he thought chronic criminal conduct may be a disease.

"It's hard to tell. And yet you can get some families of four kids where three are doing beautifully and the fourth is a chronic armed robber," Harris said.

Asked if he thought some people were "inherently evil," Harris responded: "There is such a thing as a bad person, and that's part of the problem.

"Some people . . . you can't get back. They are chronic offenders, they are going to be chronic offenders and society has to be protected against these people until they reach the point in their lives where they are no longer a menace to society," Harris said.

At the same time, he said he would not discount the possibility that some offenders can benefit from efforts at rehabilitation.

Many of the questions about criminal conduct belong outside the law enforcement role of the prosecutors and remain in the hands of criminologists, Harris said.

As U.S. attorney, Harris supervises more than 150 prosecutors who work both in the U.S. District Court and in the D.C Superior Court, where the vast majority of the city's criminal cases are filed. The local court has traditionally been weighed down with a massive caseload that Harris said is most acute in the misdemeanor section, which handles the least serious criminal cases.

He said he would support a proposal that the D.C. City Council reduce the penalty for some crimes, such as petty larceny, to a level that would preclude defendants from demanding time-consuming jury trials.

Harris said he believes that plea bargaining in more serious felony cases is a necessary tool for reducing the court's caseload and that without it "the system cranks to a halt."

But, he added that in cases involving violent crime, the prosecutor's office must take a "pretty hard-nosed attitude" toward plea bargaining and resist lowering the charges against a defendant simply to close a case.

Harris said he would also favor a change in bail law to allow Superior Court judges to set high money bonds for defendants who they believe pose a danger to the community if they are released from custody before trial.

Current law says that money bonds can be set only if a judge believes that a defendant will not show up for the next scheduled court appearance. If danger is a question, the prosecutor's office must request a pretrial detention hearing and ask that the court hold the defendant without bond.

Within his own office, Harris said he was "basically not in favor" of proposals that the U.S. attorney's office transfer the bulk of its prosecutorial authority to a new local prosecutor. Most observers believe that the proposal, supported by the Carter administration and Harris' predecessor, Charles F.C. Ruff, has no chance of backing by a Republican administration.

"I think we have a wonderfully corruption-free prosecutorial system here," Harris said, adding that his philosophy is "if it ain't broke, don't fix it."