The U.S. Marshals Service, with dual responsibilities to the federal courts and the Justice Department, is being operated under "unworkable" management conditions that lead to inefficiency in most operations, according to an investigation by the General Accounting Office.

The GAO, which acted at the request of Sen. Max Baucus (D-Mont.), recommended that all law enforcement duties be transferred to other agencies in the Justice Department.

"Dual authority requires marshals to faithfully conduct distinct missions for two branches of government, but without any agreement between the branches on the priority of the various . . . functions," the report said. "As a result, marshals establish their own operation priorities."

The marshals serve a number of functions for the judiciary, acting as guards during court sessions and delivering subpoenas and fugitive arrest warrants.

For the executive branch's Justice Department, the marshals transport prisoners and operate the witness security program, which relocates and provides new identities for people testifying against organized crime.

The GAO concluded that the witness program, which has been widely criticized, suffers from major problems because of the dual jurisdiction.

"The witness security program is inefficient, program services have been delayed, and the safety risk for witnesses has increased," the report said.

In its response to the GAO investigation, the Justice Department argued that "there is no dual authority" in the U.S. Marshals Service and that although there are some "management problems" they could be solved by increasing the budget.

The GAO also found major problems arising from the fact that the U.S. marshals are appointed by the president and have some political autonomy, while the deputy marshals are career civil servants who work for the attorney general.

The GAO provided the example of a political appointee who refused to reassign a deputy responsible for compromising the identity of several protected witnesses relocated to his area. As a result, the Marshals Service had to relocate two of the witnesses to other areas and is no longer sending witnesses to that jurisdiction.

The marshals' record on apprehending fugitives was also criticized by the GAO. "Because of dual authority, fugitives are frequently not actively pursued, and established investigative procedures are often not followed . . . increasing the potential for the commission of new crimes while the fugitives remain free."

The GAO recommended that the marshals restrict their duties to their court-related functions and that law enforcement functions, such as the fugitive and witness programs, be transferred elsewhere in the Justice Department.

In a related study, the GAO found that the marshals are continuing to perform the outdated duty of serving subpoenas for private lawsuits at fees far below what private process servers are charging.

During the 1980 fiscal year, the marshals served 353,000 subpoenas and other court documents for private individuals at a loss to the government of up to $4.7 million. While the marshals charge $3 for such services, private companies were charging up to $45.

The GAO recommended that the marshals use certified mail for delivering the documents in many cases and that, when documents must be delivered in person, the fees be raised to eliminate any loss to the government.

The study also found that the marshals are unnecessarily transporting prisoners on commercial airlines in many cases. Those flights are not only much more expensive than the charter flights regularly scheduled for the federal prison system, but also subject the public to unnecessary risks, the GAO found.