The Defense Department is jeopardizing the independence of a proposed "Star Wars" think tank by inviting only select scientists to establish it and by insisting on a voice in choosing senior personnel, Sen. Carl Levin (D-Mich.) said last week.

Levin also said that the Pentagon is creating "enormous potential for abuse" by refusing to enact "revolving door" prohibitions against scientists moving from the institute to private companies whose performance the institute will evaluate.

The Pentagon announced in March that it intends to create a government-funded, nonprofit institute to provide advice on the Strategic Defense Initiative, similar to the way the Rand Corp. advises the Air Force. SDI, also known as Star Wars, is President Reagan's $3-billion-a-year research program aimed at developing a defense against nuclear missiles.

The think tank proposal drew criticism from opponents of the controversial SDI program, who said creation of an institute will make it more difficult for future presidents to end or diminish the SDI program if it proves unwise. They also said the institute will allow Lt. Gen. James A. Abrahamson, SDI director, effectively to increase the size of his staff at higher-than-government salaries.

Abrahamson said in an April 16 letter to Levin that the institute is intended to offer "objective, conflicts-free advice" in a way that private industry could not.

"The purpose is precisely to avoid any bias, unintentional or otherwise, in evaluating SDI-related technology for a future national decision by the responsible authorities on a strategic defense program," Abrahamson wrote.

But Levin said that Abrahamson and Defense Secretary Caspar W. Weinberger may be guaranteeing a pro-SDI bias in the way they are structuring the institute. The senator, who said he was acting as ranking minority member of the Governmental Affairs subcommittee on oversight of government management, cited these concerns:

*Abrahamson said Weinberger "has invited certain prominent individuals in the science fields" to form the organization, but the general did not identify them. Levin said that apparently no one else will be invited to bid.

"If so, the public and the Congress have a right to know who has been extended the privilege of dealing with the federal government on a sole-source basis concerning a long-term contract," Levin said.

*Levin said Abrahamson intends to help choose the center's dozen or so top staff members, which would represent an "unprecedented" level of control. Most federally funded research centers, such as the Logistics Management Institute in Bethesda or Rand's Project Air Force in California, are largely free of such control by the agencies to which they report, Levin said.

"Scientific objectivity and independence from political considerations are particularly important for the Strategic Defense Initiative program," Levin wrote. "This program has aroused serious academic debate as to its technological feasibility."

*Levin also criticized the administration for not writing rules that would prevent institute officials from moving to companies they have helped regulate. He said the institute will spend much of its time reviewing industry proposals and research.

"This review function creates an enormous potential for abuse," Levin said, adding that employes could recommend a contract award and "six weeks later accept a job with the firm that submitted the 'winning' proposal."