The House Assassinations Committee suggested yesterday that the mysterious "Raoul" supposedly involved in the killing of Martin Luther King Jr. might really be one of James Earl Ray's brothers or "a composite of the two of them."

The committee's chief counsel, G. Robert Blakey, aired the theory to begin what proved to be a long and rancorous hearing with Ray's fast-talking younger brother, Jerry, as the only witness.

Testifying under a court-ordered grant of immunity which he invoked only once, Jerry Ray, 43, and his two lawyers repeatedly denounced the allegations and accused the committee, in turn, of a variety of unfair tactics.

One of the attorneys, Florynce Kennedy, a black who openly called her client "a redneck racist," charged that the committee seemed bent on ignoring any information that might exonerate the Rays. The other, William Pepper, assailed the panel for pouring unverified and unsworn allegations into the public record and calling on Ray to respond under oath.

Blakey opened by saying the committee had pursued every lead it could concerning James Earl Ray's insistence over the years that he was somehow lured into taking part in the April 4, 1968, assassination by a shadowy character named "Raoul."

"All leads on Raoul were pursued on the assumption that such a man might indeed exist," Blakey said. But, he added, "when you come down to it, the Raoul theory that seems to fit is that the mysterious accomplice might actually be one of Ray's brothers, Jerry or John, or a composite of the two of them."

The committee produced four charts indicating, as Blakey put it, "that at each point where James' movements or his funding during the fugitive period are explained by James by reference to Raoul, one of the brothers is, in fact, either on the scene or in contact with James."

Blakey offered these examples:

When James Earl Ray moved from Canada to Birmingham, Ala., in the summer of 1967, after his escape from the Missouri State Penitentiary that year, he claims to have met at the Detroit-Windsor border with Raoul "who paid him $1,500 for helping in a smuggling operation." "This was supposed to have occurred on August 21 (1967)," Blakey said. Yet, he added, "on Aug. 22, from accounts given by both James and Jerry, we know the two brothers met in Chicago." Moving to Birmingham, Ray bought a 1966 Mustang and some camera equipment with money that he has said he got "from Raoul in Birmingham in August."

In a conversation with a committee witness who asked for anonymity, "Jerry Ray has admitted he was in New Orleans with James in December (1967)." James Earl Ray, Blakey reported, "claims it was Raoul who gave him $500 in New Orleans on Dec. 17" of that year. But on his return to Los Angeles, where he was then living, "he told a dancing instructor of a recent meeting in Louisiana with his brother."

Once again, on March 29, 1968, according to James Earl Ray, he and Raoul went to Birmingham where Ray says he bought a rifle with $750 "given to him by Raoul" and then exchanged it the next day.

"Ray claims... that Raoul rejected this rifle and told him to exchange it for another model," Blakey pointed out, "but when Ray telephoned the (rifle) salesman... he said he had learned he had purchased the wrong type of rifle from a conversation with his brother."

For his part, Jerry Ray denied that he was "Raoul," and insisted that he met with brother James after the 1967 prison escape only in Chicago and the Chicago suburb of Northwood. Jerry Ray said he feels convinced that "Raoul is still out there" somewhere. The witness said he feels strongly that the King murder was the result of a conspiracy in which James Ray was "unknowingly involved," but he couldn't be more certain than that.

"The only was I could say there definitely was [a conspiracy] would be if was involved in it," Ray observed.

Ray invoked the Fifth Amendment only once, when questioned about remarks he allegedly made to George McMillan, author of a book on James Earl Ray called "The Making of an Assassin." McMillan supplied the committee with typewritten notes of his interviews with Jerry Ray.

According to one passage, Ray told McMillan in a May 30, 1972, interview that brother John Ray saw James Earl Ray the day before James escaped from the Missouri penitentiary and that "Jack went down to pick him up after the escape."

Again purporting to be quoting Jerry Ray directly, McMillan's notes said that all three brothers, John, Jerry and James, met in Chicago "the next day after the escape" and Jerry "was ready with money" for James.

Jerry Ray at first refused to say whether he had made such remarks to the author. "I'd like to invoke the Fifth Amendment on all this stuff," he told committee counsel Mark Speiser.

Directed to answer under the court-ordered grant of immunity, Ray told the committee only that "I don't remember saying anything like that" to McMillan. Under continued questioning, he said ne occasionally fed McMillan false information "now and then to get him off my back," including falsified entries in a banking account and a phony set of "Ray family" pictures that Jerry Ray procured from an album that some donor had given to the Salvation Army.