Cracking cold cases in Florida: How Sunshine State Sonar does it

Florida accounts for roughly 6% of all cold cases in the United States, meaning that some 20,000 families are still wondering where their loved ones are, according to government information.

But there’s a group called Sunshine State Sonar, that hopes to help those families.

“We work with cold case detectives on these cases of missing people where their vehicles have not been found. And we specialize in these kinds of cases, and we go out and try to follow the footsteps of their last known whereabouts," said Mike Sullivan, founder of group.

On a September day, NBC6’s Sophia Hernandez finds Sullivan with his brother John Martin and friend Shelly McKinney, off West Sample Road in Coral Springs.

Last month, they were in Coral Springs looking for the body of Steven MacKrell, who went missing in July of 2015.

The families live their lives not knowing what may have happened.

“It is something they live with their entire life, always wondering what happened to their loved one,” said Sullivan.

That Friday morning Sullivan, Martin and friend Shelly McKinney were following on MacKrell’s footsteps. They were looking for a vehicle that might give them a clue as to what happened.

As he was walking along the sidewalk, Sullivan looked into a thick brush.

“There will be spots of brush like this where a vehicle could have gone in and it’s just so far back it’s not visible from the road, and so we are looking for those soft spots and when we see them we are walking 150 feet into the tree line,” Sullivan said.

For an hour, the team of three conducts their land search. From the outside looking in, you may think they are part of a law enforcement agency.

But they are just regular people wanting to help.

“Shelly is a tattoo artist by trade but works at a hospital right now as a receptionist. My brother John owns a pool company, I own an auto parts company. And some of our other guys are a fitness trainer, the other one owns a construction company. We are all just a big group of friends, we get together, we do this it’s like fun for us,” said Sullivan.

Martin explained they are trying to help solve a case "to give closure" to a family.

McKinney, who lives in Virginia, had already been researching cold cases on her own. Her special skill set is that she is the ‘mapper’ and the lead background researcher.

She wanted to do more with her knowledge.

“I reached out and said, ‘Hey, if you want I can help you out and map out some areas, areas that need to be searched, accident areas.' And we just went from there,” McKinney said.

So that’s how this self-funded group of volunteers got together. At a minimum, they try to spend roughly one weekend a month trying to solve a cold case in one area of Florida.

“It just feels like you are contributing to something bigger than yourself, like you want to leave something behind that is important and does good. There is so much negativity in the world, I feel like being able to come out here as volunteers, is important. There needs to be more of that,” McKinney said.

PIECES OF A PUZZLE

After not finding anything in the woods, the crew decided it was time to visit another area. So they check their map and decided to drive to a new spot 10 minutes down the road, where they did what they do best: underwater searches.

Their small but mighty sonar boat, according to Sullivan, has helped solve 11 cold cases since 2022, and has helped to find 12 people in the last 20 months.

“It’s like putting together the pieces of a puzzle. But you know you read about the cases, you hear about the cases, and even ones that don’t involve vehicles. And I think it’s just a compassion thing because you see families, you see how much they hurt,” said McKinney.

“After the first case we solved, I think that’s what really fueled us, because it was like OK, we can do this. We are capable of making a difference in people’s lives.”

Sullivan and McKinney took the boat out for a ride and came back with news: “We have a submerged car right here under the bridge.”

The team used a magnet to mark the spot and then came out to dive and get a closer look to see if anyone is inside the car, and grab the license plate details.

After diving, Sullivan described the vehicle as a red Nissan, that didn't match the description of MacKrell’s case, but that could be related to another cold case.

In those cases, McKinney says that’s when they pass it along.

“We will call law enforcement and tell them what we found, what it could be. Especially if it matches the case car we are looking for. We are hands off, we contact them, and let them handle it,” she said.

Sunshine State Sonar says they have a good working relationship with most law enforcement agencies, but sometimes they get pushback for their work.

In any case, sharing the news with the families is usually the hardest part.

“It’s emotional. There’s a lot of times where it takes a while for it to hit us. But to talk to the families and to put yourself in their shoes, that it’s one of our own family members, it gives us the passion to want to go out there to give that family member the closure they are looking for. Even though it’s not what they want to hear, it’s bittersweet. At least they know, and that gives us the passion to do that for them,” said Martin.

While the team didn’t find anything that time around, they kept searching the next three days in different areas. After the weekend was done, they found seven vehicles, but none were related to their case.

But the work in searching for missing persons never stops.

Sullivan says they are determined to bring closure to families, and bring loved ones home.

“We just hope that they find peace and they have a resting spot for their loved one, and it fills in those blanks and answers of where they were 20, 30, 50 years,” he said.

They plan to continue working the MacKrell case this week, down in the Everglades, where they will consider any and all possibilities.