For the first time in more than four years, Cpl. Lindsey Scott took the witness stand in his defense yesterday, but he appeared confused and shaken during questioning.

Scott's testimony came on a procedural question, and the jury of seven Marine officers was not in the courtroom at the time. But his responses to a barrage of questions by the chief Marine prosecutor led most courtroom observers to speculate that Scott's attorneys will not allow him to testify again in his trial for rape, kidnaping, attempted murder and sodomy.

In 29 minutes on the stand, Scott contradicted the previous testimony of three naval investigators, and stumbled over answers to questions about his actions on April 21, 1983. That was the day Scott emerged as the primary suspect in the previous day's attack on the wife of a military policeman at Quantico Marine Corps base, about 35 miles south of Washington.

In the end, the defense lost the critical procedural battle, and a Quantico police officer was allowed to testify that Scott told him he had wiped off the passenger side inside of his car -- where the attack allegedly occurred -- because he didn't have time to clean the whole car.

Scott denied in his first court-martial in 1983 that he had wiped down any portion of the car. The police officer did not testify at that proceeding.

In other testimony yesterday, the office manager of a Dumfries apartment building where Scott lived said Scott borrowed a serrated steak knife on the day of the attack, and never returned it to her.

The knife, which Scott said he used to clean his stove, has never been recovered; Scott said he accidentally threw it away.

The court-martial under way at Quantico is Scott's second. At the first trial in 1983, he was convicted and sentenced to 30 years at hard labor. Scott had served nearly four years of that term when the nation's highest military court set aside the verdict last summer on grounds that his previous civilian attorney had not prepared a competent defense.

By far the most compelling part of yesterday's proceedings -- the eighth day of Scott's court-martial -- came after his attorneys moved to suppress the testimony of the police chief of the town of Quantico, located in the midst of the sprawling Marine base.

After the jury left the courtroom for the procedural hearing, Police Chief Leo Rodriguez described how he had happened by the base's criminal investigation division, where Scott worked, in the late afternoon of April 21, and found investigators searching Scott's car.

Rodriguez said -- and several investigators have testified -- that he noticed the passenger side of Scott's car appeared to have been wiped down. Prosecutors have suggested Scott did this to erase forensic evidence.

Rodriguez said he turned to Scott and asked him: "Why did you only clean {the passenger} side? He said, 'That's all the time I had.'"

Scott's attorneys said the remark should not be allowed as testimony before the jurors because Rodriguez did not advise Scott of his rights before striking up the conversation, and because Scott had broken off another interview with investigators, telling them he wanted to speak to a lawyer.

To answer the question of whether Scott had asked to speak to a lawyer, attorney Gary R. Myers called Scott to the stand.

Myers questioned Scott only briefly; then the military prosecutor, Maj. Ron McNeil, went on the attack. McNeil fired questions at Scott.

Scott stumbled over several of his answers while Myers jumped to his feet, objecting repeatedly but without success.

Scott said at first he didn't understand one of the questions, then acknowledged having spoken with the NIS agents, adding that it was not a "full-fledged conversation." He denied the testimony of three previous witnesses who said Scott had requested to speak with two NIS agents who he knew.

Asked whether he knew his rights under the Constitution at the time, Scott responded, "Yeah."

Responding to a question from the military judge, Lt. Col. Eligah D. Clark, Scott said he did not remember seeing or speaking with Rodriguez during the search of his car.

After about an hour's deliberation, Clark allowed Rodriguez to testify before the jury, ruling that Scott had made the statement voluntarily after having been advised of his rights earlier in the day.

In the defense's cross examination, Myers pressed Rodriguez as to why he had not testified at the 1983 court-martial. Rodriguez said he had told one of the investigators (he did not remember whom) about Scott's remark, but that he was not contacted about testifying.

Another witness who was in charge of the NIS investigation, Richard W. Wardman, testified that several days after the attack, he drove the woman and her husband through several parking lots until she asked him to stop, got out and identified a vehicle in which she said she was raped. The car turned out to be Scott's.

Myers, indignant, suggested that the woman's husband, who worked with Scott and might have known he was a suspect, could have described Scott's car to her before they went looking for it.