As far back as January, a D.C. lobbyist for Chicago Mayor Brandon Johnson estimated the city would need as much $76 million to help pay for Chicago Police overtime, salaries and equipment to provide security for the Democrat National Convention, according to emails obtained by NBC 5 Investigates.

The email thread between the then-D.C. lobbyist for the Johnson administration and a Congressional aide suggested that Chicago would spend as much as $25 million on Chicago Police overtime, another $10 million on salaries and $25 million on equipment, including a new helicopter, body cameras and additional items like van rentals and body armor.

The email thread also shows the $76 million request for a Department of Justice grant went “above and beyond any grant amount previously requested.”

Included in the email thread, the lobbyist shared a Politico article that referenced a clash between pro-Palestinian protesters and D.C. police.

The Congressional aide wrote back: “This is exactly why we’re prioritizing this funding.”

A spokesman for Johnson and the city’s budget office both said cost estimates for the DNC were not available and could take a week or two to tabulate.

Additional security cameras and fencing were installed after protesters breached a section of the fencing on the north security perimeter about two blocks north of the United Center where the DNC was underway.

“That’s really troubling for me. It’s just a lot of money,” said Freddy Martinez with the Lucy Parsons Lab, which has studied police surveillance and equipment for years. “It raises questions about how are these decisions being made. And do community members have any input into how we want to see our city in the future. So that’s like a big concern for us.”

NBC 5 Investigates asked Chicago Police Supt. Larry Snelling about the costs and the criticism.

“Well, first off, I know, I don’t handle the finances, so I’m going to leave that part of it alone. But what I will tell you is this: When it’s necessary to protect the city, you have to make the investment. When we’re looking at officers who are out there putting their lives on the line every day, those officers who are out there putting their safety at risk every day, leaving their families at home. The investment in keeping this city safe is absolutely necessary,” Snelling said.