A 25-year-old Northeast Washington man who is charged in a double homicide was mistakenly transferred from the D.C. Jail to a halfway house as part of the city's emergency effort to reduce the jail population under threat of a court order.

Fennell Goodman III, who was being held on a charge of felony murder, was about to walk out the door of the halfway house last Friday when corrections authorities realized their error and returned him to the jail, a law enforcement official said.

U.S. Attorney Joseph E. diGenova said the error "disturbed and deeply concerned him." In addition, since the transfers began last Friday, about a dozen persons sent to halfway houses have escaped, another law enforcement official said.

While these incidents underscore some public safety concerns with the transfer program, interviews yesterday with both corrections personnel and persons who live near halfway houses indicated an apparent degree of acceptance of the program.

"You don't even know they are there," Bessie Little said of the prisoners assigned to the halfway house at 1010 North Capitol St.

"I hope it stays that way," said Little, a drugstore clerk who lives within a few yards of the four-story brick halfway house.

Transfer of inmates from the overcrowded jail to the halfway house on North Capitol Street and to the seven others around the city is an important part of the city's effort to prevent enforcement of an order by U.S. District Judge William B. Bryant.

On July 15, citing "massive overcrowding," Bryant ordered the city to send no new prisoners to the jail, starting Aug. 24, unless the inmate population was cut to 1,693.

On Aug. 22, the city won a reprieve by promising to reduce the jail population by nearly one-third in the next 90 days through such measures as speeding up paroles, releasing more people awaiting trial and urging judges to reduce prison sentences as well as sending prisoners to halfway houses.

When Judge Bryant issued the order, there were nearly 2,600 inmates in the jail. Yesterday's figure was 2,082, jail officials said.

Shortly after the emergency effort began, James F. Palmer, head of the city's corrections department, joined other city officials in offering assurances that dangerous criminals would not be released and that the public safety would not be endangered.

In last Friday's incident, Goodman, the murder suspect, was transferred from the jail to the North Capitol Street halfway house in the belief that he was being held in connection with a conviction for possession of marijuana, according to a law enforcement official.

However, according to court records, Goodman was being held without bond in the January 1984 fatal shootings of two men behind a recreation center in far Northeast Washington. In a court document, prosecutors said the shootings were carried out in execution style.

After the transfer, a review of his file indicated the mistake, the law enforcement source said, and an emergency call was placed to the halfway house.

Most halfway house residents generally spend their days outside the house, working or looking for jobs, and Goodman, according to the source, was on his way out when the call came. He was returned to the jail, and diGenova said he was investigating the incident.

Rodney Tyson, a counselor at the halfway house at 1430 G St. NE, indicated that the staff there has managed to cope with the sudden increase in population from 40 to 85. "We anticipated a problem with the new arrivals," he told a reporter yesterday, "but we have had none since they arrived."

Cornelius Shell, 33, who lives on the same block as the halfway house, also appeared unflustered. "They put this halfway house in a neighborhood which can handle itself, " he said. " . . . We don't bother them and they don't bother us." Another neighborhood resident, Clara Herndon, past president of the G Street block club, said there had been no untoward incidents so far. But, she said, she was unhappy about not being consulted about the moves. The city, she said, "should have told us in advance."