Federal authorities announced Friday that a key immigration enforcement program that has drawn protests from some state and local governments will offer greater protection to crime victims and witnesses.

Through the Secure Communities program, the FBI shares the fingerprint data of people arrested by local and state law enforcement agencies with federal authorities, who can use the information to check for immigration violations. Immigrant organizations have complained that the program does not distinguish enough between minor offenders and serious criminals. They say there is widespread concern the program would silence victims and witnesses, who are often reluctant to report crimes for fear of being swept up in arrests and tagged for deportation.

“It is agency policy not to put these people into immigration proceedings,” said John Morton, director of Immigration and Customs Enforcement.

The changes provide for greater prosecutorial discretion, which Morton said “expands the grounds and the circumstances to be considered when officers are making decisions on who to detain or remove.” Reforms include more training for local law enforcement, greater agency oversight and a stronger complaint system.

“If the administration is really concerned about their image in the community, what they should do is to suspend the program completely,” said Gustavo Andrade of Casa de Maryland, an immigrant advocacy group.

Massachusetts, Illinois and New York recently said they would pull out of the program. Baltimore and Oakland, Calif., also voted to cancel participation.

“We don’t take that lightly. We take the governors’ concerns seriously, and that’s part of the reason why these reforms are being undertaken,” said an ICE official with knowledge of the program. But the program is an “information-sharing agreement between federal agencies,” and there is no room for local jurisdictions to opt out, he said.

The program, which began in 2008, has been implemented in 50 percent of the country — about 1,400 jurisdictions — with a goal of having it in place nationwide by 2013. An advisory committee, which includes law enforcement officials and immigration advocates, is expected to review it and offer findings by August.

Some immigration groups were cautiously optimistic. “We’re pleased that there’s been an acknowledgment of flaws” in the program, said Brittney Nystrom of the National Immigration Forum. “It’s a good sign, but the real devil here is in the details.”