A task force on violent crime has recommended that Attorney General William French Smith ask the Navy for aid in fighting drug traffickers, help turn over abandoned military bases to states to ease prison overcrowding, upgrade the search for 40,000 violent fugitives, and take a stand on urging local police to enter violence-prone public schools.

The recommendations are among 15 contained in an interim report of the task force Smith created in April to increase the federal effort against violent crime. Others include: a form of computerized data bank some civil libertarians fear could be the forerunner of a national network, a push to improve the usual five-week processing of fingerprint checks, and various steps to establish better coordination between state and federal law enforcement agencies.

These 15 steps could be taken immediately without additional funding or changes in legislation. Smith is expected to announce some of the recommendations he has approved in a speech Tuesday to the FBI Academy at Quantico.

It is clear from the recommendations that the task force has come down on the side of law enforcement in the balancing act between police powers and privacy. However, Jeffrey Harris, executive director of the group, said the task force members recognized civil liberties concerns in their deliberations.

The task force is chaired by Carter administration attorney general Griffin B. Bell and Illinois Gov. James R. Thompson. It has held public hearings in Washington, Los Angeles and Atlanta so far and has more scheduled for Chicago, Detroit, Miami and New York. In August the group is to prepare more recommendations that require changes of law or added funding.

A closer look at some of the major recommendations:

To permit use of the Navy in drug interdiction, the so-called Phase I report notes a loophole in the Reconstruction-era Posse Comitatus Act designed to keep the military out of domestic law enforcement. The law now forbids the Army and Air Force from such interference, but doesn't mention the Navy.

The Pentagon has opposed earlier suggestions that it go outside its military mission and said so at a House hearing this week on a bill that would authorize what the task force recommends.

Use of abandoned military bases for easing prison overcrowding on an "interim and emergency basis." About half a million people are behind bars in the United States, about half of them for violent crimes. About 190,000 of the prisoners are in state facilities, which are constantly being sued on complaints of poor conditions. The task force doesn't intend to use the military barracks as an alternative to needed new construction of prisons, the report emphasized.

The number of fugitive warrants outstanding totaled more than 180,000 nationally in April, with 42,000 for violent offenders. The FBI turned major responsibility for finding fugitives over to the U.S. Marshals Service in 1979 and had only about 1,600 active investigations of fugitives at the first of the year, Director William H. Webster told the task force.

The report said the task force was concerned about low priority given to locating fugitives and competition and lack of coordination between state and federal authorities.

"Crime has reached epidemic proportions in a substantial number" of public schools, the report said. It noted that a 1977 national survey showed that two-thirds of all robberies and half of all assaults on youths from 12 to 15 occur at school, and that 5,200 teachers were physically attacked each month.

School officials seem "either unable or unwilling" to deal with crime, the report said, and called on Smith to make it a national issue. It said the attorney general shouldn't assume responsibility for policing schools but his leadership might encourage local officials to deal with the problem.

An FBI experiment to establish an Interstate Identification Index should be carried out. It would provide user states with names, but not the criminal histories, of offenders. Harris said that in its next phase the task force will study whether to push for the more controversial idea of a national data bank, where the FBI keeps the actual criminal histories. Members of Congress and civil liberties groups have fought that plan for years.

The report also recommends exploring a separate registry of firearms violators to forewarn police officers, continuing efforts to train local officers, and expanding the crossing of jurisdictions by local and federal prosecutors to handle some investigations.