Some members of the federal jury that Thursday convicted eight Christian activists of helping smuggle illegal aliens were sympathetic with the defendants' cause and distressed when no witnesses were presented by the defense, one juror has said.

At the same time, an attorney for one defendant in what has become one of the harshest church-state clashes in U.S. history said the defense made "a terrible mistake" in allowing a former federal official on the jury after being told, incorrectly, that she had recently changed her party registration from Republican to Democrat. The juror, Catherine A. Schaefer was elected foreman and reportedly strongly influenced the guilty verdicts, which could mean prison terms of up to 25 years for two Roman Catholic priests, a nun, a Presbyterian minister and four lay workers.

David McCrea, one of the few jurors willing to discuss the case, said that Schaefer argued that the judge's instructions and the law required some guilty verdicts. McCrea, an employe at an electrical parts plant who often worked a seven-hour evening shift after his day in court, said he and some other jurors "sympathized with the defendants and didn't agree with the law, but we had to follow the law and had to follow the instructions."

He said he tried to look for holes in the evidence that would allow some acquittals and was disappointed when the defendants decided to rest their case without taking the stand or presenting witnesses. "It would have been better if they had presented the other side," McCrea said in an interview Thursday night.

Three defendants and three of their attorneys said they think that little would have been accomplished by presenting a defense. Michael Altman, attorney for Sister Darlene Nicgorski, said that "in any long, complicated trial, testimony gets confused," and defense witnesses could have cast doubt on some prosecution statements. But once on the stand, he added, the defendants could not deny "they were involved in helping refugees in many ways."

Their only sure defense, the defendants insisted, was to try to persuade the jury that international law, the 1980 Refugee Act and the desperate situation in Central America permitted help for the refugees. But U.S. District Court Judge Earl H. Carroll ruled out such arguments as irrelevant to what he called "a simple smuggling case."

"We kept hearing references to the 1980 Refugee Act," McCrea said, "but it wasn't allowed to be admitted." The Sanctuary Movement, begun by defendants Jim Corbett and the Rev. John M. Fife here in 1982, was not familiar to many jurors when they were selected in October. McCrea said then he thought a sanctuary was "for birds."

Robert J. Hirsh, Fife's attorney, said he was so distraught after what he thought should have been a complete acquittal "that I couldn't go to work today." He said "we made a terrible mistake" by allowing Schaefer on the jury. He declined to say who provided the false information about her party registration, but called Schaefer "a quintessential bureaucrat" who chose to give the need for reasonable doubt in order to vote for acquittal "a very strict interpretation."

Schaefer has a bachelor's degree in financial administration, attended law school for one year and once administered federal grants to local governments here. Stopped by reporters as she tried to drive away from the courthouse Thursday, she repeatedly said "I don't want to discuss the case."

The national movement to give sanctuary to Central American refugees claims the support of more than 250 churches, at least 12 cities and the state of New Mexico. Backed by the Presbyterian, Methodist and Lutheran denominations, the movement has raised $1.4 million to fight the court case and supported a news media office here with four paid staff during the seven-month trial. Thomas E. Ambrogi, coordinator of the National Sanctuary Defense Fund in San Francisco, said that about 30,000 people have contributed money and that he expects more support now, because of the guilty verdicts.

Fife, whose little Southside Presbyterian Church is the center of the movement here, remained cheerful after the verdict. Convicted of three felony counts, which could mean as much as 15 years in prison, he told his mother by telephone Thursday that "federal minimum-security prison is no Auschwitz. It's going to be a distinct improvement in my life style."

Corbett was acquitted with fellow Quaker lay worker Nena MacDonald and Catholic lay worker Mary K. Doan Espinoza. He said today he continued to help refugees throughout the trial and could be indicted again.

His attorney, Stephen W. Cooper, has left for Brownsville, Tex., to defend another Sanctuary worker, Stacey Lynn Merkt, on a retrial. His previous conviction was overturned on a technicality.

Assistant U.S. Attorney Donald Reno said Thursday that the government will continue to enforce the immigration laws but declined to say if more indictments are imminent.

Defense attorneys said they are confident of victory on appeal. Some suggested that Carroll, immigration laws having been endorsed by the jury, may void the convictions on the grounds of selective prosecution -- the charge that the government unconstitutionally used the case to quiet criticism of refugee policy and failed to prosecute similarly Arizona growers who use illegal immigrant labor.

Altman said he is eager to argue that government undercover agents unconstitutionally infiltrated churches. "It's a law professor's dream," said Altman, who teaches at Arizona State University. "There are no cases on point."