Determining Liability for a Legionnaires’ Disease Outbreak

Who Can Be Held Responsible for a Legionnaires’ Outbreak?

One of the most important aspects of any Legionnaires’ disease lawsuit is identifying who is liable – in other words, who’s at fault for the conditions that allowed Legionella bacteria to flourish and make people sick. Legionnaires’ cases are typically very complex. Investigations include complicated and technical evidence and often multiple parties are involved in managing a building or water system. This page explains how we determine liability in Legionnaires’ outbreaks and ensure the right people (or companies) are held accountable.

What Does “Liability” Mean in Legionnaires’ Cases?

“Liability” means legal responsibility. In a Legionnaires’ disease context, we’re typically talking about negligence:

Did a person or organization have a duty of care to keep water safe? (For example, a hotel owes its guests a duty to provide safe premises, including water.)
Did they breach that duty by doing something wrong or failing to do something necessary? (for instance, not maintaining their hot tub, ignoring water system guidelines, not cleaning their HVAC cooling towers, etc.)
Did that breach directly cause exposure to Legionella bacteria that led to illness?

If the answer to these is yes, that party is liable for the harm caused.

Legionnaires’ disease usually falls under premises liability (because the bacteria is present at a location under someone’s control) and sometimes under product liability (if equipment is defective) or professional negligence (if a water treatment firm or lab messes up). But most commonly, we are holding property owners/operators liable for failing to keep their water systems safe.

Because Legionella bacteria can spread long distances in the air, in certain cases (contaminated outdoor fountains, HVAC cooling towers, etc.) exposure can take place at some distance (sometimes miles) from the initial contaminated water source.

Investigating the Source: The First Step

Before assigning blame, we must confirm the source of Legionella. Often this is done by public health authorities:

Health Department Investigation: In many outbreaks, local or state health departments investigate once Legionnaires’ cases are reported. They test water samples in places patients visited, inspect maintenance logs, and sometimes even perform DNA sequencing of the bacteria to see if patients’ strains match environmental strains. Their reports can be pivotal evidence. For instance, if the health department report finds Legionella in a building’s cooling tower and concludes it’s the likely source, that’s strong support for liability against the building.
Our Independent Investigation: We don’t rely solely on others. Our legal team often hires environmental engineers or industrial hygienists to conduct an independent investigation. We might obtain water testing records, depose (question) maintenance personnel, review construction blueprints (to identify design issues), and analyze patterns (did all victims visit one part of the building?). We are often looking for clues that an official probe may have missed.
Linking Patients to the Site: We gather evidence that you (our client) were at the location in question during the risk window. Receipts, hotel records, witness statements, work timesheets – whatever shows you were present where and when the exposure likely occurred. This ties your case to that site’s liability.

Once the source is confidently identified (say, a hotel’s hot water system, or an apartment building’s faucet, etc.), we look at who had control and responsibility over that source.

Identifying All Potential Defendants

As mentioned in our Lawsuits section, there could be several. We systematically consider:

Property Owner: The entity (individual, corporation, government, etc.) that owns the building. Often liable as the primary responsible party.
Property Manager or Operator: If the owner is hands-off and hires a management company (common with hotels, condos, malls), that company might be responsible for day-to-day maintenance failures.
Maintenance Contractors: Any third-party companies contracted for specific tasks – for instance, HVAC maintenance firms for cooling towers, pool service companies for hot tubs, water treatment service providers for adding chlorine, etc. If they were hired to prevent exactly the hazard that happened, they’ll be scrutinized.
Manufacturers/Installers: Consider if any equipment malfunctions contributed. Did a brand of water filter fail prematurely? Was a new construction not up to code? These are less frequent angles, but we check.
Legislative or Compliance Breaches: While not “defendants,” if a building violated laws (for instance, some cities require quarterly cooling tower cleanings and the building skipped them), that violation itself is evidence of negligence (a concept called negligence per se in legal terms). We leverage any regulatory breaches to bolster our case against the defendants.

Example: Suppose a luxury spa had a decorative fountain in the lobby that caused an outbreak. The investigation finds the fountain’s water was rarely changed or chlorinated. The spa is owned by “Spa Corp” but managed by “Elite Resorts Inc.”, and they had a maintenance contract with “WaterWorks LLC” to service all fountains monthly (which clearly didn’t happen). In this scenario, we might sue Spa Corp and Elite Resorts for overall negligence (they had the duty to ensure water safety), and include WaterWorks LLC if evidence shows they failed in their contracted duties. Everyone will likely point fingers at each other – but that doesn’t matter for the victim; they can be held jointly liable.

Proving Negligence (What Did They Do Wrong?)

Once we have the defendants lined up, the focus is proving what each did wrong. Here are common failures in Legionnaires’ cases:

No Water Management Plan: In this day and age, not having a plan is itself a sign of negligence, especially for hospitals, hotels, and other high-risk buildings. We’ll ask in discovery, “Did you have a Legionella control plan? Show us.” If they don’t, it looks bad for them.
Ignoring Guidelines or Codes: Many industries have guidelines (OSHA, CDC, state health codes). If a nursing home didn’t conduct required water tests or a cooling tower didn’t have the mandated maintenance, that’s clear evidence.
Poor Maintenance Records: We look at maintenance logs. Sometimes we find outright falsification (e.g., records claim checks were done that employees admit under oath were not). Other times, logs show long gaps (no entries for months) or recurring issues that were never fixed (e.g., “temperature low, needs adjustment” noted repeatedly with no follow-up).
Prior Incidents or Warnings: If that building had a prior Legionella positive test or previous case and did not take adequate corrective action, it strongly establishes negligence. Many outbreaks are preceded by warning signs. We’ll dig into whether any prior guest or resident was diagnosed and whether the defendants knew about any Legionella detections before the outbreak.
Training and Knowledge: We may question if the staff had training about Legionella prevention. If not, it shows a corporate negligence in not educating those responsible for maintenance. If yes, did they implement it?
Equipment Failures: Was a piece of equipment (like a chlorinator) broken for a long time? Did alarms (like low disinfectant alarms) go off and get ignored?
Documented Complaints: Sometimes guests or residents complain about water quality (smell, discoloration) before an outbreak. If such complaints were made and shrugged off, that’s evidence.
Expert Evaluation: We’ll have experts review everything and testify that in their professional opinion, the defendant’s maintenance was substandard and fell below what a reasonably prudent operator would do. They compare the defendant’s practices to industry best practices to highlight the shortcomings.

All these elements build the narrative: “This outbreak was not a fluke; it was the predictable result of the defendant’s failure to take basic preventive measures.” We show the court that if the defendant had done what virtually everyone in the industry knows should be done, people would not have gotten sick.

What If Multiple Parties Are Liable?

It’s common that more than one party shares blame. Legally, the concept of joint and several liability may apply – meaning each defendant can be held liable for the full amount of damages, leaving it to them to sort out contributions. As plaintiff’s attorneys, we cast a wide net to ensure our clients can recover from whoever has the ability to pay and is at fault.

For example, if a hotel and a maintenance contractor are both liable and the hotel’s insurance is insufficient to cover the verdict, the contractor might cover the rest (depending on state law). We basically want to avoid a situation where a single defendant can’t pay the judgment. So, including all responsible parties protects the client’s ability to collect the full compensation.

In court, defendants might argue about comparative fault (saying others are more to blame) – sometimes even trying to blame the victim (which is generally absurd in Legionnaires’ cases, since how could a guest be at fault for a hotel’s bacteria? But they may claim the person’s own home was the source, etc.). We defend against such tactics by solid evidence linking their site to the illness and showing the victim did nothing wrong (one can hardly avoid breathing the air at a building they visit).

Using Experts and Scientific Evidence

Proving liability in Legionnaires’ cases often comes down to science. We work with top experts, such as:

Microbiologists/Epidemiologists: To explain how the outbreak likely originated and spread, often by doing a source analysis. If multiple people got sick, an epidemiologist can show a statistical link to a location (for instance, “all victims stayed at Hotel A – the odds of that cluster happening by chance are minuscule, indicating Hotel A is the source”). They can also address DNA fingerprinting results if available (showing the strain in the water matched the strain in patients).
Engineers/Industrial Hygienists: To speak to the building’s systems and maintenance. An HVAC engineer can testify how a cooling tower aerosolizes water. An industrial hygienist might discuss how water stagnation in unused floor pipes could breed bacteria. They basically connect the dots between poor maintenance and contamination.
Medical Experts: To rule out other potential sources in a patient. For example, a pulmonologist might testify that based on the incubation period and patient history, the patient most likely inhaled Legionella during the hotel stay and not elsewhere.
Water Management Experts: There are consultants who specialize in Legionella prevention; they can tell a jury what the standard of care was and how the defendant deviated from it.

By presenting expert testimony, we translate technical maintenance failures into plain English for a judge or jury: “This cooling tower was a ticking time bomb because XYZ wasn’t done, and eventually it went off, causing this outbreak.”

We may also introduce visual aids: diagrams of a water system, timeline charts of what was done or not done, photos of dirty cooling towers, etc. Such evidence can be compelling in establishing negligence clearly.

Real-World Example of Liability Established

To illustrate, let’s consider a hypothetical (based on real patterns): An outbreak at a Chicago apartment complex sickens 8 people. Our investigation finds the complex’s outdoor decorative fountain had zero chlorine when tested and the water was murky. Maintenance logs reveal the fountain’s filter system broke 6 months prior and was never fixed; maintenance simply refilled water but never properly cleaned or chlorinated it. Management emails show cost-cutting delays in repairs. In this case:

Duty of care: Apartment owes tenants and visitors a safe environment.
Breach: Clear breach – broken filtration, no chlorine for months, against guidelines.
Cause: Epidemiologist shows all 8 sick people spent time around that fountain area, genetic testing matches Legionella in fountain to patients.
Damages: 8 people with hospital bills, etc., some with long recovery.

Liability here would firmly be on the apartment owner/manager for negligence. They might try to claim a maintenance vendor was responsible for fountain upkeep; if so, we’d rope that vendor in too. But all evidence points to blatant neglect. A case like this would likely settle favorably once we present these findings, because the defendants know a jury would be appalled at the indifference.

How Liability Affects Your Compensation

Establishing liability is not just about blaming; it directly ties to whether you get compensated. In legal terms, without proving liability, there’s no recovery. That’s why our firm leaves no stone unturned in investigating these cases. When we take on a Legionnaires’ case, we’re committed to proving it, not just alleging it.

Once we clearly establish who’s liable, the pressure is on the defendants to compensate our clients appropriately. Strong liability evidence often leads to larger settlements because the other side recognizes that at trial, they’re likely to lose and possibly face even higher payout (plus bad publicity).

Our Experience in Proving Legionnaires’ Liability

Our legal team has developed a blueprint for handling Legionnaires’ disease cases thanks to extensive experience:

We know the right questions to ask in discovery (sometimes defense counsel is surprised at how much we already seem to know about their client’s systems – that’s experience at work).
We are familiar with common excuses defendants use and how to counter them. For example, a hotel might say “But we’ve never had Legionella issues before!” We counter that with how negligence over time can lead to a first-time outbreak, and lack of prior issues is not a defense against current negligence.
We’ve built relationships with expert witnesses who are leaders in the field of Legionella control. When we bring them in, defendants know the testimony will carry weight.
We have a library of past case documents and research. This helps if we face a repeat scenario (many Legionnaires’ cases have similarities – for instance, we’ve seen multiple “cooling tower at a hotel” cases, so we know what evidence tends to exist and where to find it).

By entrusting your case to us, you benefit from a team that can quickly zero in on liability and build a compelling argument. We understand that for you, the bottom line is getting justice and financial recovery – and that hinges on our ability to prove someone else was at fault. Rest assured, that’s exactly what we set out to do in every case we handle.

Get Clarity on Who’s to Blame – and Hold Them Accountable

If you’re unsure who might be responsible for your Legionnaires’ disease, that’s normal. These situations aren’t obvious to laypeople. Leave the detective work to us. During a free consultation, we’ll listen to your story and give you an initial take on who could be liable. We might ask questions like where you stayed, if any health officials contacted you, etc., to gather clues.

Even if it’s not immediately apparent, once you hire us, we deploy our resources to figure it out. You deserve to know why you got sick and who could have prevented it. Most importantly, you deserve to not shoulder the financial burden of someone else’s negligence.

Contact us at 1-888-377-8900 or reach out online, and let’s start uncovering the answers together. If there is a liable party, we will find them – and we will pursue your rightful compensation from them aggressively.