Boston's DA, US attorney escalate legal spat over man detained by ICE mid-trial

The legal battle between state and federal law enforcement over the detention of a man by U.S. Immigration and Customs Enforcement in the middle of his criminal trial in Boston last week escalated on Wednesday, through court filings and heated words from both sides.

The district attorney for Boston called what happened "unacceptable and unprofessional" and said that the actions of the agency are undermining work to ensure public safety in the city. The Massachusetts's top federal prosecutor shot back, in letters to Suffolk District Attorney Kevin Hayden and the judge in the case, that there are no legal grounds for bringing charges against the ICE agent — he's already been charged with contempt of court.

The matter revolves around William Martell-Lebron, who was taken into federal custody in the middle of his trial last week and not returned for court the following day. Boston Municipal Court Judge Mark Summerville later dismissed the case in state court over prosecutorial misconduct, and found ICE agent Brian Sullivan in contempt.

“We simply can’t have ICE trampling on our criminal legal system. That’s a problem," Hayden told reporters Wednesday morning.

But U.S. Attorney for Massachusetts Leah Foley told Hayden in a letter Wednesday evening that his "office must cease from entertaining or pursuing any charges against Officer Sullivan or any other federal official relating to the arrest," and, referring to his news conference, said "it is inappropriate to suggest to the public that federal officers can be criminally prosecuted by your office or any other state or local prosecutor’s office for performing their official duties" while noting that interfering with an immigration officer's efforts to execute the law is a felony offence.

And to Summerville, the judge who earlier this week called the "disturbing case" a serious matter of "violating a defendant's right to be present at trial and confront witnesses against him," Foley said that the Constitution's Supremacy Clause makes federal officers working in their official capacity immune from prosecution in state court.

"While you might disagree with the enforcement of our federal immigration laws, there is simply no legal basis for you to hold federal officers in criminal contempt for carrying out their sworn duties. Any attempt or threat to interfere with the lawful functions of federal government agents will not be tolerated," Foley said in the letter.

What DA Hayden said at Wednesday's news conference

Hayden said the case was, to his knowledge, the first time such interference had arisen and that it could not be tolerated again. He also criticized ICE's larger actions, saying recent enforcement policy is having a "chilling effect" on the communities that local law enforcement rely on to ensure public safety.

"We’re now finding witnesses reluctant to cooperate with investigators due to fear of ICE. This harms public safety. We are seeing victims refuse to provide information about crimes against them due to fear of ICE. This harms public safety," Hayden said.

He noted that Boston is the safest major city in the country and said the efforts of his office and their partners are part of the reason for that.

He added that his office can neither support nor interfere with ICE during their operations, and that he hopes they will offer reciprocal respect for local operations.

"If ICE interferes with the operation of our duties, as happened here, we’re going to speak out about it," Hayden said.

Hayden said that his office is in contact with its federal partners, including ICE, about this particular case and is "cautiously optimistic" that in the future they will work together on public safety.

A spokesman for ICE did not return a call seeking comment.

Read U.S. Attorney Foley's letters to Hayden, Judge Summerville

Foley's office released these letters along with a statement from Foley noting that her office had moved in federal court to vacate the contempt order, citing a lack of "authority to issue the unlawful and erroneous order" — more on that motion below.

What Martell-Lebron's lawyer says

Martell-Lebron's Andover-based attorney, Murat Erkan, said Wednesday that he doesn't believe Hayden's claim that his office had nothing to do with ICE detaining his client, calling that claim "gaslighting."

And citing a state trooper's testimony that Sullivan told the state prosecutor about plans to detain Martell-Lebron during a break in the trial, he concluded, "Somebody lied. There's no doubt about it."

Hayden said flatly about the attorney in his office, "he didn't lie," and the judge decided the actions were due to inexperience, not malice.

"I blame the DA's office more for the lack of training than these young [assistant district attorneys] who got themselves put in that situation," Summerville said at the hearing this week.

Justice Department says contempt charge should be dismissed

The contempt ruling against ICE agent Brian Sullivan was referred to the Suffolk County DA's office, meaning Hayden will review the case to determine whether any charges should be filed.

The Justice Department filed a motion Wednesday in federal court supporting Sullivan’s effort to dismiss the contempt charge. It argued that the state court lacked the authority to “issue that patently unlawful and erroneous order.”

“This damaging state intrusion into federal functions is the precise harm that the Supremacy Clause guards against,” U.S. Attorney Leah Foley said in the motion. “The state court’s order disregards bedrock principles of federalism and inflicts an unacceptable burden (and ongoing threat of criminal prosecution) on a duly authorized federal official. This Court should immediately vacate the state court order.”

Immigration officers were a growing presence at courthouses during Trump’s first term, prompting pushback from judges and other local officials. The president has gone further in his second term by repealing a policy in place since 2011 for agents to generally avoid places such as schools, houses of worship and hospitals.

Under current policy, immigration officials can make arrests “in or near courthouses when they have credible information that leads them to believe the targeted alien(s) is or will be present” and as long as they are not prohibited from doing so by state or local law.

“The fact that this arrest occurred in between trial days during the Commonwealth’s prosecution of Defendant — and thus, in the state court’s (mistaken) view, violated Defendant’s right to attend his trial — does not alter the analysis,” Foley said. “The whole point of Supremacy Clause immunity is that federal law — not state law, state authorities, or state proceedings — must govern the conduct of federal officials in carrying out their federal duties.”

What happened after ICE agents detained Martell-Lebron last week

Martell-Lebron was detained by ICE agents outside of court on Thursday, after the start of his jury trial on charges of providing false information on a license application, as The Boston Globe first reported.

ICE has said they grabbed Martell-Lebron on the first day of his trial because he's really Juan Carlos Baez, a Dominican Republican resident previously convicted of drug trafficking.

"That was the purpose of the trial was to determine whether or not the government could prove that," argued Murat Erkan, Wilson Martell-Lebron's attorney.

Summerville had held an emergency hearing on the matter Friday, where he ordered ICE to return Martell-Lebron, who is now being held in federal custody in Plymouth, to court to stand trial on Monday.

Erkan on Monday called what had happened obstruction of justice and alleged a plan involving the state to deport Martell-Lebron. Erkan said that all it took was an email for ICE agents to show up at previous hearings, yet they ignored the order to appear in court Monday.

During the hearing, Summerville repeatedly overruled objections and threatened to throw out the lawyer for Assistant District Attorney Jack Lucy.

Lucy was called as a witness, where he admitted that ICE agent Brian Sullivan shared his intention over the phone the day before the trial to take Martell-Lebron into custody. Lucy said he met with Sullivan and two state troopers during a break the next day, and Sullivan said they would take him at the end of the trial.

"Prosecutors from the Suffolk County District Attorney's Office had no knowledge that the defendant was going to be arrested that afternoon," Assistant District Attorney Cailin Campbell said in court Monday.

Hayden doubled down on that message Wednesday, saying that his prosecutors acted ethically and will continue to do so.

“There is no credible evidence, none whatsoever that our prosecutors knew that ICE was going to move Mr. Martell-Lebron in the middle of the trial," Hayden said.

The judge found that Massachusetts State Police troopers played a role in letting ICE know when Martell-Lebron would be leaving court.

"There was a plan in place," Summerville said at the hearing. "There was an operation place."

"This is a plan to stop the defendant — to disappear him — during his ongoing jury trial so that he can't defend himself," Martell-Lebron's attorney said.

ICE released a statement Tuesday morning, saying "Officers with ICE Enforcement and Removal Operations Boston field office apprehended Juan Carlos Baez (aka Wilson Martell-Lebron), a 49-year-old, illegally present Dominican national with prior drug trafficking convictions, after he departed the Boston Municipal Court March 27, 2025.”