OMAHA — A new group that includes a former governor and the president of a labor union that sued U.S. Immigration and Customs Enforcement plans to renew investigations of the agency’s tactics during workplace immigration raids.

The group of experts and leaders in law, labor and civil rights includes former Iowa Gov. Tom Vilsack and will be led by Joseph Hansen, president of the United Food and Commercial Workers International Union. They plan to report any findings of misconduct to Congress this summer.

“Everything that I learned in grade school and high school … is being trampled on by ICE and it just needs exposure,’’ Hansen said Friday.

The group plans to hold hearings across the country to investigate how ICE conducts operations at workplaces and the consequences they have on workers’ lives.

The first hearing was planned for Monday in Washington, where group members expected to hear testimony from immigration experts and workers who were in Swift plants during raids in 2006.

Hansen said he invited Julie Myers, director of ICE, to Monday’s hearing.

ICE spokeswoman Pat Reilly said she could not confirm whether Myers was invited or planned to attend the hearing, but said the agency’s policies protect its officers and would hold up against the scrutiny of any group.

“They know that they are in the spotlight,’’ Reilly said. “The standards protect them.’’

Vilsack said he hoped to investigate allegations of ICE agents violating constitutional rights of workers and suggest possible changes to ICE policy.

“Many of the misdeeds that we’ll be able to identify and talk about did not occur to people who weren’t properly here; they occurred to people who were legally here all their lives, people who were born here or people who immigrated properly to this country,’’ Vilsack said. “That’s what concerns me.’’

ICE officials investigating identity theft arrested 1,297 workers at six plants during the Swift operation, but union officials have said that more than 12,000 workers were detained against their will. Swift has estimated the financial impact at up to $50 million.

“Unfortunately it’s a crime scene,’’ Reilly said. “It isn’t a nuisance. The American people want us to do this. They want us to know who’s in this country and why they’re here.’’

Hansen’s union filed a federal suit against ICE in September, accusing the agency of mishandling the Swift raids and seeking an order to stop what it called illegal workplace raids. The case is still pending in federal court in Amarillo, Texas.

The plants raided were in Grand Island, Neb.; Cactus, Texas; Greeley, Colo.; Hyrum, Utah; Marshalltown, Iowa; and Worthington, Minn.

The union organized the investigatory group and invited Vilsack and other leaders to join. Among the group members are Mary Bauer, director of the Southern Poverty Law Center’s Immigrant Justice Project, and Samuel Kyles, an influential Baptist pastor in Memphis, Tenn., who was with Martin Luther King Jr. when he was assassinated nearly 40 years ago.

Kyles said he joined the group because of his ties to Hispanics in Memphis, and compared the group’s investigation to King’s work.

“Anywhere people are fighting for their rights, they have no problem using Martin Luther King as a model and they’re right in doing that,’’ Kyles said. “It’s a part of the dream, and the dream is still unfolding.’’

Brazilian firm JBS S.A. acquired Swift from a private equity firm for about $1.5 billion in July, making the company the world’s largest beef processor.