Among last week's confirmation hearings on President-elect Jimmy Carter's Cabinet appointments, none generated more heat than the Senate Judiciary Committee's examination of Attorney General-designate Griffin B. Bell.

But the hearings shed remarkably little light on how Bell, as the incoming administration's top legal officer, plans to approach the broad range of problems and issues facing the Justice Department.

That's because Bell's controversial two-decade record as a lawyer and federal appeals court judge involved in the South's desegregation battles caused the hearings to focus almost exclusively on his attitudes toward civil rights.

It was the subject of overriding concern to the long parade of witnesses who appeared before the committee. And it was the subject that dominated the questions by comittee members.

As a result, Bell, in his two days of testimony, never got very far beyond repeatedly asserting his commitment to vigorous civil rights enforcement. As one spectator put it. "About the only thing he didn't do was sing 'We Shall Overcome'."

In the process, everything else got such short shrift that Sen. Charles McC. Mathias Jr. (R-Md.) was moved to remark: "We really have developed little or no information about so many other aspects of the Attorney General's duties that impinge on the lives of all Americans."

Civil rights enforcement, for all its importance and visibility, is only one of these duties. As Attorney General Bell will be responsible for administering laws and programs that range over areas as diverse as crime prevention, antitrust policy and the use of federal land and natural resources.

In addition to running the various devision of the Justice Department, he also will have policy direction and control over several subsidiary federal law enforcement agencies including the Federal Bureau of Investigation, the Law Enforcement Administration, the Bureau of Prisons and the immigration and Naturalization Service.

Yet the hearings, which are scheduled to conclude Monday, have given few clues about Bell's thinking in regard to these responsibilities. What sketchy information he did provide indicated that, in many key areas. Bell has still to familiarize himself with the practical workings of the Justice Department and the problems it must solve.

One subject that he did dicuss at the length is the problem of bringing the FBI under a control that will prevent the abuses that shattered the Bureau's morale and reputation. Even there though. Bell did little more than indicate, in deliberately fuzzy language, that he intends to ease out FBI Director Clarence M. Kelly and replace him with his own man.

Bell also said that he planned to restructure the Justice Department in a way that would put the deputy attorney general, as yet unnamed, in charge of overseeing all the subsidiary law enforcement agencies such as the FBI.

The idea is regarded as naive by many veteran Justice Department source. They note that outgoing Attorney General Edward H. Levis was forced to spend the majority of his time on FBI's problems and they add that those problems remain so pressing that Bell will be inviting potentially big trouble if he tries to delegate responsibility for FBI oversight.

On a related subject, Bell said he was thinking of transferring at least some of the responsibility for combating the traffic in narcotics to the FBI. However, he didn't specify whether that would mean disbanding the Drug Enforcement Administration or merging it with the FBI.

That too has caused law enforcement sources to talk about his lack of familiarity with "the real world." They point out that the FBI historically has shown great reluctance to get into the anti-narcotics field.

The sources also noted that DEA, which was founded three years ago largely because of the FBI's lack of enthusiasm, recently has started to show signs of getting an effective grip on the drug problem. To abruptly change direction now, the sources fear, might undo the progress that has been made in drug law enforcement and foster a virulent new outbreak of the narcotics problem.

Another tricky issue that will confront Bell involves the question of whether to continue attacking organized crime through the use of Justice Department strike forces. These are a Johnson-era innovation that combines investigators from several agencies into a single unit to probe racketeering in several cities.

However, they have irritated the U.S. attorneys in the cities where they operate: and the recent trend within the department the strike forces.

Bell, in his testimony, hinted that he agress with this move. He said that having a strike force fixed in a city "sitting around looking for business" is akin to having "two U.S. attorneys' offices competing with each other."

instead, he said that he favors using strike forces not as fixed entities in specific cities but as special mobile groups that can be moved around to conduct investigations in different areas as the need arises.

He took a somewhat similar tack when questioned about his views on a permanent special prosecutor's office that would pursue official wrongdoing independently of the Justice Departments. Instead, he said, he would prefer legislation spelling out areas of investigation and circumstances that would "automatically trigger" the activation of a special prosecutor when the need arises. However, he did not elaborate on how this would be done.

In the era of civil liberties, Bell said he thought the death penalty was "warranted in some cases." But, he added, "the use of the death penalty has been abused in the past, and it should be used sparingly."

"I haven't worked out in my mind yet just what cases it should be used in," he said, "but I lean toward such special circumstances as the killing of a prison guard or death resulting from a plane hijacking."

On another civil liberties question - whether there should be a law prohibiting wiretapping in national security cases unless approved by selected federal judges - Bell tentatively took a different tack from his predecessor.

Levi has refused to conclude that the President does not have a right to order electronic eavesdropping without a warrant in cases involving foreign intelligence. Bell said he leaned toward the idea that a warrant should be required for all wiretapping, but he qualified his answer by saying that he wanted to study the matter in more detail before committing himself.

Bell agreed with questioning senators that efforts should be made to insulate the Justice Department from political involvement. In this respect, he promised to maintain a stringently kept log of all contacts between department officials and the White House or members of Congress.

Bell also said that, if he is confirmed as Attorney General, he will disqualify himself from any role in the next two presidential elections, whether he is in public office or not. But he seemed to disagree with suggestions that there should be legislation specifically barring anyone who has served in a candidate's presidential campaign from appointment to the Attorney General's office.

One somewhat novel idea advanced by Bell involved the antitrust field. He said that existing laws are adequate to protect the public from monopolistic practices, but added that the system too often breaks down because of the time consumed in getting complex antitrust cases through the courts.

"You can beat the system if you can keep the case in the courts, for years," he said. And he added that, as Attorney General, he might go into court personally in come cases "to get them moving."