The shooting is raising new questions about the U.S. Secret Service's timing that day, and overall resources equipping the agency to perform its duties.
The Secret Service has only been protecting presidents since 1901, after Republican President William McKinley was shot dead by an angry anarchist.
While the investigation into the assassination attempt continues, some are questioning whether the Secret Service is equipped and funded to meet the new, present day challenges it faces.
"The biggest challenge for the agency was being under resourced," said John Koskinen with the National Academy of Public Administration, a nonpartisan group of experts that is commissioned by Congress to study federal agencies.
In 2019, Koskinen led a group of experts in an 18-month study of the Secret Service's workforce.
The group's findings were released in a 2021 report titled, "Building for the Future: Employee Engagement in the United States Secret Service."
The study found, "Secret Service employees are asked to do more than ever within tight resources," and that, "Threats against the President and other protectees have grown in intensity and scale with the emergence of new technologies and the heightened level of violence in the country."
The Secret Service's most recent annual report, released last year, states the agency has 33 former officials or candidates receiving protection, but that number could be higher given the current campaign underway, and the agency's legal requirement to protect all major presidential and vice-presidential candidates and their spouses.
While that number may sound small, Koskinen says you have to keep in mind all of the family members, and traveling that goes into Secret Service protection.
That protection comes from the Secret Service's workforce.
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The ABC7 I-Team found the Secret Service's workforce of full-time employees has grown slightly over the past two decades by 27%: from 6,516 employees in fiscal year 2005, to 8,296 employees in fiscal year 2025, according to a review of Department of Homeland Security's budget reports released annually.
The agency's annual budget grew from $1.3 billion in FY 2004, to $3.1 billion in FY 2024, the records show.
While watching the tragedy unfold this past weekend, Koskinen said the agency's resources crossed his mind.
"As I watched, really the tragedy unfold, and thank goodness, it wasn't worse, it did pass through my mind," Koskinen said. "This is a difficult time for the service."
Officials tell the I-Team the Secret Service has to rely on law enforcement partnerships in providing the level of security needed for campaign-related events.
Koskinen agrees.
"I don't know what's gone on in the last three years, what the resource demands on the agency are, and their capacity and ability to meet it. They always rely on, have to rely on local, state and local law enforcement officials. But even then, they have to be supervised," Koskinen told the I-Team.
Last weekend, local police in Butler County, Pennsylvania, were so strapped, they couldn't even put a squad car near the building where the shooter ended up.
Shots were fired 20 minutes after Secret Service snipers first spotted a man with a rifle on a nearby rooftop, according to law enforcement officials and lawmakers briefed on the timeline.
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Secret Service officials say the gunman, Thomas Crooks, had actually aroused police suspicion more than an hour before the shooting, yet no law enforcement on-scene followed up.
University of Michigan Professor, and national security expert Javed Ali told the I-Team that partnership and planning between the Secret Service and local law enforcement agencies will be a top focus in the investigation moving forward.
"[The Secret Service was] operating under the assumption that, you know, the state and the local law enforcement had the primary mission for maintaining that outer security perimeter. And that is clearly where the breakdown happened: that handoff between the Secret Service, state and local law enforcement, and the communication."
Ali continued, "This is what the Secret Service needs to go back to the drawing board for."