Michael J. Brown, lawyer for Gilgo Beach killer Rex Heuermann, talks about his client, the evidence and path to a plea

For nearly three years, Michael J. Brown searched for weaknesses in the case against accused Gilgo Beach serial killer Rex A. Heuermann.

In the end, the defense attorney said, his client no longer saw a path forward and directed his attorneys to negotiate a guilty plea.

In his first extensive interview with Newsday in the hours after Heuermann was sentenced Wednesday, Brown described the evidence as overwhelming and said a recovered planning document was among the most damaging pieces of proof prosecutors assembled.

"There's no way of winning this case," Brown said Heuermann ultimately realized. "He saw the writing on the wall."

This week's sentencing represented for many the final chapter of Suffolk County's most consequential criminal case in decades, one of the biggest fixations of the nation's current true crime craze. For Brown, the sentencing marked what appears to the end of his involvement in a case he built his career toward but never saw coming.

The case followed him around the courthouse — ever since his client was arrested — while also handling DWI and assault cases that keep his Central Islip law office busy. Strangers recognize him as the man sitting beside the Gilgo Beach serial killer.

"This is a worldwide case," Brown said. "I wasn't expecting that type of attention and that type of focus."

Ninety-minute decision

Brown followed the decadeslong investigation like most Long Islanders, but he said it never crossed his mind that he would represent the man often referred to as "the Long Island Serial Killer."

"I never thought they would catch him," said Brown, 59, who has practiced law in Suffolk County since 1993. "As time went on, I think it became less and less of a possibility."

That changed when he received a call from the county's assigned counsel program on July 14, 2023, telling him Heuermann was in custody and asking if he would handle the arraignment later that day.

The married father of four grown children, two of whom have followed him into the legal profession, had about 90 minutes to decide. Some fellow attorneys warned him it might be too much to take on, but his wife believed it was something he'd "thrive on." He believed that to be true.

"If you told me I would [one day defend] a serial killer with seven murder victims when I was in law school … I would love the opportunity," Brown said on the afternoon Heuermann was taken from the Suffolk County jail to Green Haven Correctional Facility, where he's awaiting prison assignment.

Attorney Daniel Russo, administrator of Suffolk's assigned counsel program, said Brown was only a handful of attorneys considered to defend Heuermann that morning.

"Mike was actually willing to put together a good team, which impressed me," Russo said.

That team would ultimately include co-counsel Danielle Coysh, while attorneys Sabato Caponi and Michael Fuchs assisted with legal challenges and Brown's son and law partner Chase Brown also lent a hand. Coysh said she also appreciated that Brown wanted to put together the best possible legal team.

The scrutiny surrounding the case was apparent from the very first day in court, Brown said. Dozens of cameras focused on him as he made his way to the courtroom to meet the Massapequa Park architect accused in the killings.

Longtime Suffolk County defense attorney William Keahon, who represented the next most recent serial killer convicted here, said Brown was the right choice to defend Heuermann. The Hauppauge-based attorney, who at 82 years old still maintains a steady caseload and observed much of the pretrial hearings in the Gilgo Beach case, was also impressed by the prosecution.

"You had the worst charges you could possibly defend and you had the best prosecutors and, I think, one of the best trial lawyers on Long Island defending with his group," Keahon said. "That's what it's supposed to be. It's supposed to be fair."

Murder charges begin to add up

Brown said he heard the same question over and over again no matter where he went: What's it like to represent Heuermann?

"It was a challenge, and it was certainly the most challenging case of my career," Brown said. "The intensity, the amount of discovery, the scrutiny. You're under the microscope." 

The intensity, the amount of discovery, the scrutiny. You're under the microscope.

— Attorney Michael J. Brown

Coysh also had the unique distinction of being the only woman at either attorney's table for each appearance by Heuermann, who she said was always respectful to her.

And as the murder charges began to add up with three women becoming four, then from six to seven and ultimately eight admitted victims, the discovery continued to pile up.

"Millions upon millions, and I have not gone through every single page," Brown said, acknowledging the work done by Coysh and others. "We had seven bodies in terms of victims in the indictment. Obviously, there's an eighth that he accepted responsibility for, and part of the investigation includes other [potential] victims … so just the discovery alone was mammoth."

As lead attorney on the Heuermann defense team, Brown was in a unique position of having examined all of the key evidence in the case.

Every tip, each far-fetched suspect, all the minor leads make their way to the defense under state discovery laws. It's not just the breakthroughs that happened late in the investigation and pointed to Heuermann that ended up in Brown's hands, but all the law enforcement missteps early on.

Closing the deal

Reviewing the case file reinforced Brown's belief that investigators failed to devote sufficient attention and resources to the killings. He said he believes the case file shows the victims' roles as sex workers and some of the people they associated with prevented them from getting "the attention they deserved" from investigators.

The early stages of the investigation date back to the murder of Sandra Costilla in 1993 and grew with the discovery of the "Gilgo Four" remains in 2010.

That changed, Brown said, following the election of Suffolk County District Attorney Ray Tierney and the creation of the Gilgo Beach Homicide Task Force, which brought Suffolk police and prosecutors together with state and federal investigators.

"It took somebody like the district attorney to actually close, seal the deal," Brown said. 

Authorities during the time of the initial investigation disputed they were slow to give the case proper attention, noting they were swamped with thousands of tips and leads, many of which turned out to be dead ends. 

Brown also credited State Police Investigator Tifini Atai's work to connect Heuermann to the suspect profile and said current Suffolk detectives, forensics investigators and FBI agents contributed strong police work to the investigation.

Tierney said it was important for the prosecution and defense to have a strong working relationship, and he credited Brown and Coysh with being professional and mounting strong legal challenges on behalf of their client. It was a challenging case to prosecute that could have been more difficult with another adversary.

"They did a really good job litigating the case until [Heuermann] said 'No more,'" the district attorney said.

'Blueprint for murder'

When Heuermann was arraigned for a third time in June 2024, investigators unveiled a long-deleted document they said allowed him to methodically plan out his kills and prepare to evade law enforcement. Sometimes referred to as a "blueprint for murder" or a "killing manifesto," the planning document he maintained in the early 2000s likely erased what little doubt of his guilt existed for most people following the case.

"That was a powerful piece of evidence," Brown said. "There's no getting around it." 

That was a powerful piece of evidence. There's no getting around it.

— Attorney Michael J. Brown, on the killing planning document

The document, which prosecutors said was deleted but recovered using forensic software, listed "problems" a killer might face like DNA, witnesses, blood stains and material evidence. It also included an outline of supplies that might be used by someone looking to kill — rope, hair nets, acid — and referenced apparent dump sites and possible future targets.

Certain details in the document were particularly challenging for the defense.

"When you saw that document, and you saw step by step … the locality, the fact that when you're talking about locations on Long Island," Brown said, referencing the inclusion of a Manorville road near where partial remains of victims Jessica Taylor and Valerie Mack were discovered.

Brown said as a defense attorney fighting for a client, you never see an obstacle as insurmountable.

"It's a challenge for me," the defense attorney said. "I find in my head, 'How do I overcome this challenge?' This was a difficult one, but you do your best."

Keahon applauded the efforts by Brown and Coysh in their unsuccessful attempt to have nuclear DNA evidence against Heuermann barred at trial. Prosecutors were up to the task in defending the evidence, he said.

Science's pivotal role

Brown and Coysh said their legal arguments regarding the modern techniques used to link Heuermann to hair found at the crime scenes were proper.

Coysh, 46, who is also a Long Island native and a graduate of Suffolk University Law School in Boston, called it a "challenging case" and said she is proud of the work they did "making headway on novel legal issues."

Keahon learned firsthand when he represented serial killer Robert Shulman at trial in 1996 just how difficult the task is.

"No matter how good you are," Keahon said. "It's an incredible amount of work and you have to do it consistently."

The gruesome nature of the evidence was another troubling aspect of the case. Brown said crime scene and autopsy photos are never easy to look at, but in a case where human remains were severed, mutilated and left to decompose, you don't soon forget what you saw.

"Even if I've seen horrific things on one case, you got to multiply that by eight, 10, 12," Brown said. "It does strike a chord."

Rex was extremely careful. He strategized, and he was very deliberate and intentional. Nevertheless, as a victim's family member said, 'You weren't as smart as you thought you were. You did get caught.'

— Attorney Michael J. Brown

The case ultimately highlights just how difficult it is to get away with a crime today, Brown said. Advancements in DNA, cellphone and surveillance technology are closing cases at a rapid rate.

"Rex was extremely careful," Brown said, "He strategized, and he was very deliberate and intentional. Nevertheless, as a victim's family member said [at sentencing], 'You weren't as smart as you thought you were. You did get caught.'"

The weight of the sins

At Wednesday's sentencing, Brown turned his body to look at each of the victim's family members as they gave impact statements to the court.

Their emotional pleas went mostly as he expected as they unleashed decades of loss, frustration and trauma on the man responsible for it all.

"They had to express themselves. I'm glad they did,"  Brown said. "It's so unique and different than the average murder case … These people have been waiting for this moment for so long."

They had to express themselves. I'm glad they did.

— Attorney Michael J. Brown, on the victims' families

The totality of the impact of his client's crimes had really set in as the sentencing hearing went on.

First a father spoke, then a mother. Sisters and cousins, sons and daughters followed. One victim after the next.

"You realize the amount of havoc that was caused and wrecked by one individual," said Brown, who limited his own remarks at sentencing to telling those family members about the impact their words and loss had on him.

When it came time for Heuermann to speak, he never used the word "sorry." Instead he focused on how his words couldn't make a difference.

Brown agreed with his client's sentiments, saying "you're damned if you do, damned if you don't."

"The sentence is predetermined," Brown said of his advice to Heuermann. "What you say is not going to matter and it shouldn't matter to these people. They have a significant loss at his hands, and you can apologize until the end of time. It's not going to make a bit of difference. Just the same, if you don't say anything … public opinion is going to be you didn't show any remorse."

When Heuermann was ushered out of the courtroom, Brown wasn't surprised or upset by the loud applause from the victims' families, who reacted like a crowd at a sporting event, the final buzzer sounding on their grief.

"They're entitled to that," Brown said.

Coysh said she thinks there's now "a sense of closure" for the victims.

"This was justice," she said. "And I'm OK with that."

Didn't face a jury

For Brown, who spent two years as a prosecutor after graduating from Boston University Law School in 1992, representing a serial killer raised a sporting analogy. It was like a deciding game in a World Series or NBA Finals, he said on the afternoon the Knicks paraded down the Canyon of Heroes to City Hall less than 40 miles away.

For attorneys, wins and losses aren't as easy to measure. And the biggest case of Brown and Coysh's lives never went to a jury. Coysh said Heuermann thanked them for the hard work they did on the case.

Brown admitted feeling a sense of relief that the sentencing was behind him, but not necessarily that it ended in a plea. While Heuermann saw the writing on the wall, his attorneys are programmed not to.

"When I took this case, I took it to try this case," Brown said. "Going back to Game 7 of the World Series or the NBA Finals, I was looking forward to trying this case, so there wasn't a sense of relief when he said I wanted to take a plea."

There will be other murder cases for Brown to try. He'll still handle his share of misdemeanors and the occasional traffic ticket, too. Nothing will top this one, he said.

"I wanted to handle the most significant, serious cases," Brown said of going into private practice 31 years ago. "I want that type of challenge."