WASHINGTON (AP) _ Congress should narrow but not kill the law that authorizes independent counsels to investigate high-ranking government officials, Iran-Contra prosecutor Lawrence Walsh said Wednesday.

Walsh, whose seven-year inquiry into arms-for-hostages trading by the Reagan administration turned many Republicans against the 1978 law, told a Senate committee the Watergate-inspired law gave credibility to investigations of presidents.

Letting the Independent Counsel Act expire on June 30 would lead to a conflict of interest in presidential investigations because the attorney general, who is appointed by the president, would oversee the inquiry, Walsh told the Senate Governmental Affairs Committee.

Many Democrats angered by special prosecutor Kenneth Starr's investigation of President Clinton and the subsequent Senate impeachment trial have joined GOP colleagues in opposing the law's renewal.

Except for a small group of moderates, the law appears to have little support.

Sen. Fred Thompson, the committee chairman, suggested Congress might consider putting the issue aside until the partisan passions from the trial subside.

``Perhaps regardless of what we do, we should wait and not try to meet the June 30 deadline,'' said Thompson, R-Tenn.

Former Sen. Howard Baker, a one-time chief of staff to Reagan, made the same recommendation last month.

But Walsh said the public would not trust an independent prosecutor's findings without some form of the current law. A special counsel should have the power only to investigate allegations of abuse of office made against presidents and attorneys general for actions during their terms, Walsh said.

The Justice Department could handle cases involving other officials, Walsh said.