Sen. Jeremiah Denton (R-Ala.) put a bill to outlaw the disclosure of U.S. intelligence operatives on a fast track yesterday and questioned the credentials of the American Civil Liberties Union in opposing the measure.

Opening a one-day hearing on the bill before his Senate subcommittee on security and terrorism, Denton deplored the lack of a clearcut criminal law to protect CIA personnel abroad and denounced "the insensitivity and moral degeneracy" of those who publish such rosters with the avowed aim of undermining the agency.

"The disclosure of the identity of a covert agent is an immoral act which cannot be tolerated," Denton said.

Jerry Berman and Morton H. Halperin, witnesses from the ACLU and its Center for National Security Studies, were the only ones to testify against the bill during the four-hour session. They said they did not condone "the practice of naming names," but maintained that the real problem is the government's "failure to provide adequate cover for our intelligence officers abroad."

Even if the bill is passes, foreign groups will still be able to identify the CIA officers in U.S. missions abroad "with a high degree of accuracy," Halperin argued. He maintained that the legislation is not only unconstitutional but is also "almost entirely synbolic."

In the questioning that followed, Denton said he didn't hear "any tittering" in the hearing room when the two witnesses described the ACLU as a "nonpartisan organizaiton" but "I think I would out in the hinterlands."

Berman defended the description, saying the ACLU takes on controversial cases crossing the entire political spectrum in its work of "defending the Bill of Rights."

Denton then brought up July, 1978, testimony by Berman on a proposed charter for the CIA, in which he recommended that "clandestine collection" of intelligence abroad by human means should be prohibited "absent any congressional declaration of war."

Berman said this was still the ACLU's position, adopted in light of a repeated pattern of "illegal activities arising from our covert capability" that came to light in the mid-1970s. But he also protested that this was not the reason for the ACLU's opposition to the bill that would make it a crime to publish agents' names, even if the information is gleaned from public documents.

Denton said he still found it "curious" that "men as intellectual" as Berman and Halperin would not think it in "our interest of self-protection" to engage in espionage and covert action when all other major powers do so.

He also questioned Halperin about a 1975 statement before the Senate Intelligence Committee in which he maintained that the United States should not conduct covert operations or covert intelligence collection by human means.

Halperin said he had had operations "abroad" in mind. In any case, he told Denton, "it is not still my current opionion."

Following the hearing, Berman told reporters that he felt Denton "showed more interest in the intentions and motives of the ACLU than in the substance of our testimony. We hope we're not entering into a pattern of going into motives and intentions."

In other developments at the hearing:

CIA Director William J. Casey reiterated his strong support for quick passage of the bill and said he could confirm after just a few months on the job that unauthorized disclosures have caused "untold damage." Casey also said he has talked with Secretary of State Alexander M. Haig Jr. about better cover for CIA officers abroad and is "getting a high degree of cooperation." He indicated that open publication of the State Department's Biographic Register may be resumed shortly, perhaps without the hints that past issues have contained about who might be working for the CIA.

Sen. John H. Chafee (R-R.I.), chief sponsor of the identities protection bill, defended its lack of a "malicious intent" clause and said he was confident it would be held constitutional.

In an opening statement, Denton voiced chagrin that "some of the journalists" who covered his subcommittee's first hearing on terrorism last month "tended to focus on an apparent lack of evidence of Soviet masterminding of international terrorism." Denton said that this was "a point of view to which no one connected with this hearing has ever subscribed." He also complained that some accounts -- he did not say which ones -- inaccurately described him as having been "surprised or disappointed" by the lack of such evidence.