The Waukesha County Sheriff Department. An audit of the department's use of data from the Flock surveillance camera system shows inconsistent reporting the reasons on the reasons investigators access the information, a problem common among police agencies. (Photo by Isiah Holmes/Wisconsin Examiner)

Like other Wisconsin law enforcement agencies, the Waukesha County Sheriff’s Department (WCSD) uses Flock cameras for many reasons, though department personnel don’t always clearly document what those reasons are. Audit data reveals that staff most frequently entered “investigation” in order to access Flock’s network, while other documented uses are raising concerns among privacy advocates. 

Flock cameras perpetually photograph and, using AI-powered license plate reader technology, identify vehicles traversing roadways. Flock’s system can be used to view a vehicle’s journey, even weeks after capturing an image, or flag specific vehicles for law enforcement which have been placed on “Be On The Lookout” (BOLO) lists.

As of March 2025, the company Flock Safety was valued at $7.5 billion, with over 5,000 law enforcement agencies using its cameras nationwide. At least  221 of those agencies are in Wisconsin, including the city of Waukesha’s police department as well as  the county sheriff . The Wisconsin Examiner obtained Flock audit data from the Waukesha County Sheriff’s Department through open records requests, covering Flock searches from January 2024 to July 2025, and used computer programming to analyze the data.

Over that period of time, more than 6,700 Flock searches were conducted by WCSD using only “investigation”, as well as abbreviations or misspellings of the word. The searches, as they appeared in the audit data, offered no other context to suggest why specifically Flock’s network had been searched. Lt. Nicholas Wenzel, a sheriff’s department spokesperson, wrote in an email statement that “investigation” has a broad usage when Flock is involved. 

“A deputy/detective using Flock for an investigation is using it for a wide range of public safety situations,” Wenzel explained. “Flock assists in locating missing persons during Amber or Silver Alert by identifying their vehicles and has proven effective in recovering stolen cars. Investigators use Flock to track suspect vehicles in serious crimes such as homicides, assaults, robberies, and shootings, as well as in property crimes like burglaries, catalytic converter thefts, and package thefts. The system also supports traffic-related investigations, including hit-and-run cases, and enables agencies to share information across jurisdictions to track offenders who travel between communities.”

Widespread use of vague search terms 

Dave Maass, director of investigations at the Electronic Frontier Foundation, says that terms like “investigation” are too vague to determine whether or not Flock was used appropriately.  At least some responsibility falls on Flock Safety itself, Maass argues. “They’re setting up a system where it’s impossible for somebody to audit it,” he told the Wisconsin Examiner. “And I think that’s the big problem, is that there’s no baseline requirement that you have to have a case related to this…They say you have to have a law enforcement purpose. But if you just put the word ‘investigation’ there, how do you know? Like, how do you know that this is not somebody stalking their ex-partner? How do you know whether this is somebody looking up information about celebrities? How do you know whether it’s racist or not? And you just don’t, because nobody is checking any of these things.”

The audit also stored other vague search terms used by WCSD such as “f”, “cooch”, “freddy”, “ts”, “nathan”, and “hunt” which Lt. Wenzel would not define.“The search terms are associated with investigations, some of which remain active,” he wrote in an email statement. “To preserve the integrity of these ongoing investigations, no further description or clarification of the terms can be provided at this time.” 

In August, Wisconsin Examiner published a similar Flock analysis that also found agencies statewide entering only the word “investigation,” with no other descriptor, in order to access Flock. At nearly 20,000 searches (not including misspellings and abbreviations), the term “investigation” was in fact the most often used term in that analysis, which relied on audit data obtained from the Wauwatosa Police Department. 

While data from the Waukesha County Sheriff’s Department appeared in that first Flock story, that analysis focused on broad trends which appeared among at least 221 unique agencies using Flock in Wisconsin. This more recent analysis focuses specifically on the Waukesha County Sheriff Department’s use of the camera network. 

The August report found that the Waukesha County Sheriff’s Department appeared among the top 10 Wisconsin law enforcement agencies that used Flock the most. The report also found that some agencies also only entered “.” — a period — in the Flock system field to indicate the reason for using the system. The West Allis Police Department led Wisconsin in this particular search term, followed by the Waukesha Police Department and the Columbia County Sheriff’s Office. 

In response to an inquiry from the Wisconsin Examiner, a Waukesha Police Department spokesperson  said that an officer who’d conducted nearly 400 Flock searches using only “.” as the reason had been provided extra training, and that the officer’s behavior had been corrected after the Wisconsin Examiner reached out. The West Allis Police Department,  on the other hand, did not suggest that its officers were using the Flock network improperly. 

Use of vague search terms is chronic across Flock’s network, Maass has found. He recalled  one nationwide audit that covered 11.4 million Flock searches over a six-month period. Of those some 22,743 “just dots” appeared as reasons for Flock searches. Searches using only the word “investigation” made up about 14.5% of all searches, he said. 

“So yeah, that’s a problem,” Maass told the Wisconsin Examiner. Reviewing a copy of Waukesha County Sheriff’s Department audit data, Maass saw the same vague search terms that have been reported by the Examiner. Although some terms can be reasonably guessed — such as “repo” perhaps meaning repossession, or ICAC, which usually stands for Internet Crimes Against Children — others aren’t so easy. 

“‘Hunt’ can mean anything,” said Maass, referring to a term which appeared 24 times within the Waukesha Sheriff’s data. Maass points to the search term “f”, which the Wisconsin Examiner’s analysis found WCSD used to search Flock 806 times. 

Maass highlights that each search touches hundreds or even thousands of individual Flock networks nationwide. “If I’m one of these agencies that gets hit by this system, how am I to know if this is a legitimate search or not?” Maass said. “Now, maybe somebody at Waukesha is going through their own system, and like questioning every officer about every case. Maybe they’re doing that. Probably not.” 

Wenzel of the Waukesha County Sheriff’s Department said that although some searches appear vague,  deputies and detectives are required by department policy to document their use of Flock in reports. Although a case number category does appear in the audit data, this column was rendered blank, making it impossible for Wisconsin Examiner to determine how often Flock searches had case numbers, or whether those case numbers corresponded with specific investigations the sheriff’s department had on file. 

“The Sheriff’s Office understands the concerns surrounding emerging technology and takes very seriously its responsibility to protect the privacy and civil rights of the community,” Wenzel said in a statement. “The use of Flock license plate recognition technology is guided by clear safeguards to ensure it is only used for legitimate law enforcement purposes.” 

The department’s policy, Wenzel explained, “prohibits any use outside of legitimate criminal investigations.” He said that deputies undergo initial and ongoing training to use the camera network. “All system activity is logged and subject to review,” said Wenzel.

Maass says the department can’t back-check the searches conducted by other agencies using the Waukesha Flock network, however. “Because when we’re talking about millions of searches coming through their system, you know, every few months…like hundreds of thousands at least every month…how are they actually quality controlling any of these?” Maass told the Wisconsin Examiner. “They’re just not.”

Wenzel said that “the technology is not used for general surveillance, traffic enforcement, or monitoring individuals not connected to an investigation.” The Wisconsin Examiner’s analysis, however, detected 43 searches logged as “surveillance” and 30 searches logged as “traffic offense.” The audit data also contained at least 357 searches logged as “suspicious” or variations of the word, as well as another 14 logged as “suspicious driving behavior,” 52 searches for “road rage” and 36 logged as “identify driver”.

There were also 62 searches related to evictions, which privacy advocates contend  go beyond the public safety roles that the cameras were originally pitched to serve.

“Evictions can be unpredictable and potentially dangerous situations,” said Wenzel. “The removal of individuals from a residence often creates heightened emotions, uncertainty, and sometimes resistance. For this reason, safety is the top priority for both the residents being evicted and the deputies carrying out the court order. Flock is utilized to determine if the former tenants have left the area or could possibly be in the area when the court order is being carried out.” 

Jon McCray Jones, policy analyst for the American Civil Liberties Union (ACLU) of Wisconsin, said in a statement that the Waukesha Sheriff’s use of Flock has extended “far beyond the public safety justifications for which these tools were originally sold.” McCray Jones told the Wisconsin Examiner, “These systems were introduced to the public as a means to reduce violent crime and aid in solving serious investigations. However, when they are used for non-criminal purposes, such as evictions, they cross a dangerous line.”  

Waukesha’s uses for evictions were particularly concerning for McCray Jones. “What’s happening here is surveillance technology, operated by taxpayer-funded public servants, being weaponized at the behest of private landlords and corporations,” he said. “That is exactly the kind of mission creep communities are most worried about when it comes to police surveillance. If Flock cameras can be repurposed to target tenants today, what stops law enforcement tomorrow from using facial recognition to track people who fall behind on rent, or phone location data to monitor whether workers are ‘really sick’ when they call off? We’ve seen documented cases where law enforcement misused surveillance systems to track down romantic interests. Once the floodgate is opened, the slide into abuse is fast and quiet.” 

Wenzel said that access to the Flock network is limited to personnel who are properly trained and authorized to use the software, and the department’s policy is regularly reviewed by those personnel. 

“Searches are limited to legitimate law enforcement purposes per department policy,” he wrote in an email statement. The department has conducted its own Flock audits, Wenzel explained, and no sheriff department staff have ever been disciplined or re-trained due to Flock-related issues. Although the Waukesha County Sheriff’s Department is part of the federal 287(g) program, in which local law enforcement agencies participate in federal immigration enforcement, Wenzel said that Flock is not used as part of the program, and the Wisconsin Examiner didn’t find any clear examples of immigration-related uses by the sheriff’s department. 

McCray Jones considers the Waukesha Sheriff’s use of Flock to be an example of why “surveillance technology in the hands of law enforcement must be tightly limited, narrowly defined, and rigorously transparent.” He stressed that every use “must be clearly logged and justified — not with vague categories like ‘investigation’ or ‘repo’, but with meaningful explanations the public can actually understand and evaluate. Without strict guardrails, audits like this reveal how quickly tools justified in the name of ‘safety’ turn into instruments of convenience or even private gain.” 

With the growth of surveillance technologies and the civil liberties implications they raise, McCray Jones said that the public “deserves clear proof that it is being used only to reduce crime — particularly violent crime — and not to serve the interests of landlords or corporations. Accountability and transparency aren’t optional add-ons; they are the bare minimum to prevent abuse.”

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A child receives a standard immunization at a Coral Gables, Fla., doctor’s office in September. Since the government shutdown began Oct. 1, the federal Centers for Disease Control and Prevention has stopped providing health surveillance data that helps state and local governments track disease trends. (Photo by Joe Raedle/Getty Images)

As the federal shutdown continues, states have been forced to fall back on their own resources to spot disease outbreaks — just as respiratory illness season begins.

The shutdown has halted dashboards and expert analysis from the federal Centers for Disease Control and Prevention, which monitors indicators such as wastewater to provide early warnings of the spread of COVID-19, influenza, RSV (respiratory syncytial virus) and other infectious diseases.

The pause leaves states with less early warning on disease outbreaks, potentially endangering lives even as child vaccination rates drop amid increased exemptions and hesitancy fed by misinformation. State and local officials can combat outbreaks with targeted advice to get vaccinated and stay home when sick, but they need to know where to do that first. And residents won’t know to take precautions if they’re unaware when many in their community are falling ill.

Wastewater is particularly crucial to finding outbreaks before people start seeking treatment, said Dr. John T. Brooks, a former chief medical officer for CDC’s Emergency COVID-19 Response who retired last year.

“This is one more piece of information to each American citizen to inform their decision, like, ‘Do I want to get vaccinated, and is now the time?’” Brooks said. “It really helps protect Americans by identifying communities where you may need to ramp up, raise awareness, remind people about hygiene.”

Ericka McGowan, senior director for emerging infectious disease at the Association of State and Territorial Health Officials, said the absence of CDC involvement “could be a problem if there’s some major issue [states] miss.” Generally, states and localities gather their own health information, but many rely on the CDC for analysis and public display.

The CDC would normally display Washington state’s wastewater surveillance information along with national and regional insights, McGowan said.  Now, the information is only available on the state’s own dashboards.

Caitlin Rivers, an associate professor at Johns Hopkins University who studies infectious disease outbreaks, checked all 50 states for shutdown-related data issues. In a Substack post, Rivers said the result of the shutdown is “DIY surveillance.”

Georgia had to pause its influenza report, which would normally start this month, because of missing CDC data. However, health officials are working on a version using only state information, said Nancy Nydam, a spokesperson for the Georgia Department of Public Health. Some hospitals report cases to the state and some directly to the CDC, so there will be some information gaps during the shutdown, she said.

In the meantime, Georgia has its own data on emergency room visits showing cases of suspected COVID-19, flu and RSV declining between August and early October.

Georgia also has its own wastewater surveillance program, which provides early warning of diseases spreading in the population before confirmed cases show up in hospitals. But some states rely on CDC wastewater surveillance.

Michael Hoerger, an associate professor at Tulane University, had to pause his state-by-state wastewater reports on COVID-19 because of the lack of CDC wastewater data and an unrelated pause in data from a private wastewater reporting collective called Biobot, he said. Biobot did not respond to a request for comment.

“The pause means that we won’t have a good sense of which states are dealing with elevated transmission [of COVID-19] until the data come back online,” Hoerger said. “I can still post useful national estimates and forecasts, but that doesn’t really help with states that are outliers from what’s happening nationally.”

Hoerger’s Pandemic Mitigation Collaborative released a report in August on COVID-19 hot spots in California, and the highest state rates for COVID-19 in late September were in Connecticut, Delaware, Nevada and Utah.

For the time being, all Hoerger can do is rely on past forecasts predicting about 499,000 new COVID-19 infections a day as of Oct. 13, the first time it’s been under 500,000 since July.

“We’re in a bit of a blackout at the moment in terms of real-time rigorous data,” Hoerger said. “Fortunately, at least nationally, we’re in a relative lull in transmission.”

Like Georgia, many states can monitor wastewater on their own to track COVID-19, flu, RSV and other diseases, according to a list compiled by Hoerger’s Pandemic Mitigation Collaborative.

Texas, for example, has not had trouble updating its data during the shutdown, health department spokesperson Chris Van Deusen said. “We do our own surveillance for most metrics,” he said. However, the state no longer gets information on new COVID-19 and RSV deaths from the federal government, he said.

North Carolina also gathers its own wastewater data and interprets it with help from the University of North Carolina and local health departments. Normally, the CDC would weigh in with its own guidance and post results on a national dashboard — actions that are paused in the shutdown, said Hannah Jones, a spokesperson for the state health department.

But even if they have their own wastewater data, other state and local health departments may rely on the CDC for analysis and guidance, said McGowan, of the state health officials group.

“Even if you collect the data, you still have to have someone who is an expert to analyze that data to give you some kind of result,” McGowan said. “A lot of localities don’t have that kind of expertise in house and they rely on the CDC for that type of technical expertise and guidance. So there’s a gap there.”

Rivers, the Johns Hopkins associate professor, wrote in her post that she sees “clouds on the horizon” in some states. There are more young children, who are most susceptible to RSV, visiting emergency rooms in Louisiana, South Carolina, Texas and Virginia, she wrote, and also more hospitalizations in Texas.

Editor’s note: This story has been updated to clarify that Washington state has its own public dashboard with updated wastewater information during the shutdown. Stateline reporter Tim Henderson can be reached at thenderson@stateline.org.

A Milwaukee PD "critical response vehicle", or surveillance van. (Photo by Isiah Holmes/Wisconsin Examiner)

The Milwaukee Police Department (MPD) is pursuing upgrades to technology used to track phones during investigations. Known as cell site simulators, the formerly murky equipment tracks phones by mimicking cell towers. Once connected to a targeted phone, cell site simulators are able to track the signal, allowing police to locate people. According to city purchasing division records, MPD aims to upgrade and acquire new components and extend a contract for the phone tracking gear by three years. 

The city’s contract with Tactical Support Equipment will be extended until 2028 and increase by $165,000 to $1.45 million. “MPD operating funds will be used,” according to records obtained by the Examiner explaining the purpose for amending the contract. The amendments will cover funds and coverage for two cell site simulators purchased in 2022, the records state. 

A separate section of the purchasing division records explains “this equipment is used on a regular basis to locate suspects and in exigent situations such as critical missing incidents.” It also states, “MPD used this equipment to help support other law enforcement agencies in Wisconsin, law enforcement in other states such as Texas, Ohio, and Michigan, and federal agencies such as FBI and DEA. At this time, MPD is seeking to upgrade the existing equipment, add additional equipment, and add warranty, support and maintenance for the new and upgraded equipment beyond what the department currently has in place. Tactical Support Equipment, Inc. is the only vendor that can support the equipment as the equipment and software is proprietary.”

MPD has used cell site simulators since at least 2010, according to logs the department uses to catalog its use of the gear. For years, the technology was used by MPD’s Fusion Center, an intelligence unit originally created for Homeland Security operations. A group of officers known as the Confidential Source Team – or CS Team – operates the cell site simulators. Logs of the technology’s use show that it’s mostly used to investigate crimes including homicides and shootings and for investigations related to overdoses or firearms. The logs also show the technology is used to locate material witnesses, kidnapping victims, but also for vague reasons like “drugs”, “long term”, or are redacted entirely.

By 2022, when Wisconsin Examiner first interviewed a member of the CS Team, both the team and its gear had been moved from the Fusion Center to MPD’s Special Investigations Division (SID), which focuses on fugitives, felonies and violent crimes. The team’s name invokes the technology’s secretive history. 

The Milwaukee department once signed non-disclosure agreements in order to acquire the technology leading to controversies in 2016, when MPD was accused of hiding use of Stingray-type devices from judges during court proceedings. When asked during a trial about how a person was located, officers used “oddly vague language,” the American Civil Liberties Union (ACLU) of Wisconsin said, even stating that they “obtained information from an unknown source.” Things have changed over time, however. Today, the Milwaukee Police Foundation, which funnels private donations to MPD, publicly lists cell site simulators as among the technologies it helps MPD to purchase.

Like many other law enforcement agencies nationwide, for years MPD utilized phone tracking equipment produced by the Harris Corporation, a multi-billion dollar defense contractor. Harris’ devices were so common that one of its brand names, Stingray, became a common shorthand for all cell site simulators, which are also sometimes called “IMSI catchers.”   

In 2019, MPD purchased a new model from Tactical Support Equipment, a North Carolina-based veteran-owned company which sells everything from K9 camera systems to cables and night-vision cameras. The company does not appear to advertise its cell phone tracking systems on its website. 

Tactical Support Equipment, which did not respond to requests for comment for this story, sold MPD a single cell site simulator in 2019 for $498,900, according to purchasing division records from the time. Later that same year, MPD purchased a C-Hostile Emitter Angle Tracker (C-HEATR), which is a remote handheld mapping device that works together with the cell site simulator. 

Three years later in 2022, MPD upgraded the cell tracking gear by adding a four-channel “5G enabler solution” for $328,700, and a 12-channel portable base station with full 5G coverage (as well as insurance, training, and supporting equipment) for $951,750. 

Responding to questions from Wisconsin Examiner, MPD said that the most recent upgrades will be to “support devices operating in 5G.” The department added that “MPD is the only agency in the area that has a [cell site simulator]. When an agency needs assistance with an investigation and their request falls in line with our operating best practices, we try to provide that agency with assistance.” 

Although cell site simulators are less of an enigma than they used to be, many questions still remain. While MPD states that its technology can only track location, cell site simulators as a family of devices are known to be capable of intercepting calls and text messages, and even more exotic abilities like sending fake short messages to a target phone. In Milwaukee, local activists have long reported strange phone malfunctions and service disruptions which they suspect may be caused by law enforcement surveillance. 

MPD has repeatedly denied responsibility for the claims, and has said in the past that the department’s cell site simulators do not cause malfunctions to target phones. When the Wisconsin Examiner reached out for this story, however, MPD said for the first time that “the equipment already will disrupt service to the target phone when the target phone is located. That disruption is limited to the time it takes for the operator to narrow down the location of the device.” 

The department has also repeatedly stated that its cell site simulators cannot intercept calls or text messages. A different technology known as PenLink is used by MPD for Title III investigations, which involve intercepting content of communications. In responses to Wisconsin Examiner, MPD cited Department of Justice policies and U.S. law which state that “cell site simulator technology must be configured as pen registers, and may not be used to collect contents of any communication.” Wisconsin Examiner reached out to the Wisconsin Department of Justice for more information and has not received a response. 

From 2021 to 2023, Republicans introduced bills that would have changed  how pen registers are defined in Wisconsin. Supporters of the bills, which did not pass, said that they would allow law enforcement to pursue pen registers for social media. Telecommunications experts, however, warned that the bills could open a “back door” for police to use cell site simulator devices in ways not well understood by judges or the public. 

There have been more calls for more oversight of police surveillance in Milwaukee recently, with local activists pushing for  Community Control Over Police Surveillance (CCOPS) ordinances. Over two dozen U.S. cities have already passed such ordinances, which provide more transparency about the purchase and use of surveillance technologies by police departments. MPD stresses that it uses cell site simulators in accordance with DOJ policy “and only after a court order is granted in cases that are not exigent,” the department said in a statement. “There is a process in place in which utilization of the equipment is only done with supervisory approval and oversight.”

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