Labor Law Defense Authority Library
The Sole Proximate Cause Defense Under New York Labor Law § 240(1)
A practical defense authority explaining the proof that separates ordinary comparative negligence from a true sole proximate cause defense—grounded in controlling Court of Appeals decisions, recent appellate authority, claims investigation, reserve analysis, and motion strategy.
New York Labor Law § 240(1) imposes substantial liability on owners, contractors, and their statutory agents when a worker is injured because an elevation-related safety device was absent, inadequate, improperly placed, or improperly operated. The statute does not, however, make defendants insurers against every construction-site accident.
A defendant is not liable when the worker’s conduct was the sole proximate cause of the accident.
That defense applies when adequate safety equipment was available, the worker knew the equipment was available and was expected to use it, the worker unreasonably chose not to use it, and the accident would not have occurred had the worker made the proper choice.
The distinction is critical:
Comparative negligence does not defeat liability under Labor Law § 240(1). But when the worker’s conduct is the only legal cause of the accident, there is no statutory liability.
The viability of the defense usually depends less on proving that the worker acted carelessly and more on proving that the defendant supplied an adequate and readily available means of performing the work safely.
Quick Answer
A worker is the sole proximate cause of a Labor Law § 240(1) accident when:
- an adequate safety device was available;
- the worker knew the device was available;
- the worker knew he or she was expected to use it;
- the worker chose, for no good reason, not to use it or misused it;
- the available device would have prevented the accident; and
- no statutory violation independently contributed to the injury.
A general instruction to “be careful” or avoid an unsafe practice is ordinarily insufficient. The defense is strongest when the record identifies a particular safety device, establishes where it was located, proves the worker knew it was available, and explains how using it would have prevented the accident.
What Is the Sole Proximate Cause Defense?
Labor Law § 240(1) requires owners, contractors, and their agents to furnish or erect appropriate devices—including scaffolds, hoists, stays, ladders, slings, hangers, blocks, pulleys, braces, irons, and ropes—to provide proper protection to workers performing covered work.
Liability is often called “absolute,” but that description can be misleading. Liability remains contingent on two findings:
- the statute was violated; and
- the violation was a proximate cause of the worker’s injury.
The Court of Appeals made this clear in Blake v Neighborhood Housing Services of New York City. The Court rejected the proposition that every ladder accident automatically establishes liability. It explained that where a ladder was adequate and properly placed and the worker was the only cause of the accident, there was no statutory violation on which liability could be based.
The defense therefore does not operate as an exception to an established statutory violation. Instead, it establishes that there was no actionable statutory violation that caused the accident.
That is why the two propositions cannot coexist:
- If inadequate protection was a proximate cause, the worker cannot be the sole proximate cause.
- If the worker was the sole proximate cause, no failure to provide proper protection contributed to the accident.
The Four-Part Court of Appeals Test
The controlling formulation comes principally from Cahill v Triborough Bridge & Tunnel Authority and was later repeated in Biaca-Neto v Boston Road II Housing Development Fund Corp.
A defendant may avoid liability when the worker:
- had an adequate safety device available;
- knew the device was available and knew he or she was expected to use it;
- chose for no good reason not to use the device; and
- would not have been injured had the worker used it.
In Cahill, the worker had been specifically instructed to use a safety line while climbing. Adequate safety equipment was available, and the evidence permitted a finding that the worker disregarded those instructions without justification. The Court held that a jury could find the worker’s conduct, rather than any statutory violation, was the sole proximate cause of the accident.
The Court of Appeals has continued to use this framework. In Biaca-Neto, it emphasized that a defendant is not liable when adequate protection was available, the worker knew it was available and expected to use it, and the worker’s unjustified choice not to use it caused the injury.
The Core Court of Appeals Decisions
Blake v Neighborhood Housing Services of New York City
Blake is the conceptual foundation of the defense.
The plaintiff fell while using an extension ladder. He testified that the ladder was securely placed, was not defective, and did not require another person to hold it. The jury found that the ladder had provided proper protection and that the plaintiff’s negligence was the sole cause of the accident.
The Court of Appeals upheld the defense verdict.
The Court explained that Labor Law § 240(1) does not impose liability merely because an accident occurred while a worker was using a ladder. The plaintiff must establish a statutory violation and proximate causation. When a worker is solely to blame, there is no statutory violation that caused the injury.
Cahill v Triborough Bridge & Tunnel Authority
In Cahill, the worker was instructed to use a safety line while climbing. The instruction had been given before the accident, and the worker disregarded it.
The Court held that a jury could find:
- adequate safety devices were available;
- the worker knew the devices were available;
- he knew he was expected to use them;
- he chose not to use them without good reason; and
- the accident would not have occurred had he followed the instruction.
The passage of time between the instruction and the accident did not eliminate the defense.
Montgomery v Federal Express Corp.
In Montgomery, ladders were available at the job site, but the workers climbed onto an inverted bucket rather than obtain one. The Court of Appeals concluded that the plaintiff was not entitled to recover under Labor Law § 240(1).
The decision is frequently cited for the principle that a worker may be the sole proximate cause when an adequate device is readily available and the worker chooses an unsafe substitute instead.
Robinson v East Medical Center, LP
In Robinson, the worker used a six-foot ladder even though he knew it was too short for the task. Taller ladders were available at the job site. He stood on the ladder’s top cap to reach his work and fell.
The Court held that the worker’s decision to use an inadequate ladder, despite knowing that an adequate ladder was available, was the sole proximate cause of his injuries.
Gallagher v New York Post
Gallagher illustrates the limits of the defense. The availability of safety equipment somewhere at the project does not establish sole proximate cause when the worker was not told where the equipment was or that he was expected to use it for the assigned task.
Biaca-Neto v Boston Road II Housing Development Fund Corp.
In Biaca-Neto, the Court applied the Cahill framework where the worker disconnected from an available safety system and took a different route to perform the work.
The Court reaffirmed that a worker’s decision to disengage from adequate protection can preclude liability when the worker knew the system was available and expected to use it.
Comparative Negligence Is Not Enough
The most common mistake in asserting sole proximate cause is focusing on the worker’s carelessness rather than the adequacy and availability of safety protection.
Examples of conduct that may constitute only comparative negligence include:
- losing balance;
- failing to maintain three points of contact;
- placing a foot incorrectly;
- moving too quickly;
- failing to ask a coworker to hold a ladder;
- standing on a wet or slippery surface;
- using a ladder in an arguably imperfect manner;
- failing to follow a general warning;
- continuing to work after recognizing a hazard.
If an absent, defective, unsecured, or inadequate safety device also contributed to the accident, the worker’s negligence is not the sole proximate cause.
The Fourth Department’s 2025 decision in Wheeler v BrandSafway Industries, LLC illustrates the distinction. The worker carried a box of wire while climbing a scaffold ladder and allegedly failed to maintain three points of contact. The court held that a jury could find the ladder failed to provide proper protection without an additional or alternative method for moving the materials. Under that view, the worker’s conduct would be comparative negligence rather than the sole cause. But the court also found a factual issue as to whether the ladder was adequate and whether the worker should have used a rope to hoist the box. The competing accounts required a trial.
Recent Appellate Division Cases: 2025–2026
Recent decisions show that the defense remains viable, but only where the factual record connects an available safety device or safe method directly to the accident.
Burgos v Darden Restaurants, Inc. — Third Department, 2025
The plaintiff was dismantling a commercial freezer and contended that he needed to work from above. The defendants submitted evidence that:
- ladders of several sizes had been supplied;
- the equipment was sufficient to perform the work from below;
- the worker had been told to dismantle the freezer from below; and
- he was instructed to contact a supervisor if a question or problem arose.
The Third Department held that the evidence raised a triable issue concerning whether the plaintiff actively ignored instructions and whether his conduct was the sole proximate cause of the injury.
Zampko v Houghtaling — Second Department, 2025
The plaintiff fell from a ladder. The defendants argued that the worker was the sole proximate cause because he failed to ask another person to hold the bottom of the ladder.
The Second Department rejected that argument. The failure to have someone hold the ladder did not establish that the worker refused to use an available safety device within the Cahill framework.
Barreto v Board of Managers of 545 West 110th Street Condominium — First Department, 2025
The First Department found factual questions concerning whether the plaintiff failed to properly position his rope grab and failed to use a rope guard. Expert evidence and coworker testimony supported the argument that the worker’s misuse or nonuse of available safety equipment may have been the sole proximate cause.
Wheeler v BrandSafway Industries, LLC — Fourth Department, 2025
As discussed above, the Fourth Department found issues of fact in both directions. The jury could find that additional protection was required while the worker carried materials up a scaffold ladder. Alternatively, it could find that the ladder was adequate and that the worker should have used a rope to hoist the materials.
The decision demonstrates that sole proximate cause often presents a jury question when the parties dispute whether the device furnished was itself adequate.
Wissert v Medline Industries, Inc. — Third Department, 2026
The Third Department again recited the Biaca-Neto elements: adequate safety equipment, knowledge of its availability, an expectation that it be used, an unjustified decision not to use it, and causation.
Bunay v One City Block, LLC — First Department, 2026
The plaintiff used a ladder to remove ductwork. His foreman testified that he had instructed the plaintiff to use a scissor lift rather than a ladder. The First Department held that the plaintiff’s own submissions raised a triable issue as to whether he was recalcitrant and the sole proximate cause of the accident.
Delisle v FBBT/US Properties, LLC — Third Department, 2026
The plaintiff gave differing accounts concerning whether he fell from a ladder or merely lost his footing and injured his shoulder while attempting to regain his balance. The Third Department held that credibility and causation issues prevented summary judgment.
Portillos v Moxie Property Solutions LLC — Supreme Court, 2026
The defendants argued that the plaintiff was the sole proximate cause because he had been instructed not to stand on a roof. The court rejected that position where the record did not establish that adequate fall-protection devices and usable anchorage points were available where the plaintiff fell.
The court distinguished a mere instruction to avoid an unsafe practice from providing an enumerated safety device.
A General Safety Instruction Is Usually Insufficient
Defendants frequently rely on evidence that the worker was told:
- not to stand on a particular surface;
- not to climb in a particular manner;
- to wait for assistance;
- to be careful;
- to avoid an unsafe location;
- to maintain three points of contact.
Those instructions may establish negligence. They do not necessarily establish sole proximate cause.
The defense becomes materially stronger when the instruction identifies a safe alternative:
- use the scissor lift located on the same floor;
- use the eight-foot ladder stored in the designated equipment area;
- connect the lanyard to the installed lifeline;
- use the rope to hoist the materials;
- remain on the scaffold platform;
- retrieve the available extension ladder before beginning the task.
The record should then establish that the alternative was adequate, operational, accessible, and capable of preventing the accident.
What Does “Available” Mean?
Courts do not apply “available” mechanically.
A device may not be meaningfully available merely because it was:
- somewhere on a large construction project;
- locked in a gang box;
- being used by another worker;
- on another floor;
- controlled by a different contractor;
- missing a component;
- unavailable without a supervisor’s permission;
- inaccessible within the time allotted;
- unsuitable for the assigned work;
- not accompanied by an anchorage point or other necessary component.
The investigation should determine:
- Where was the device?
- Who controlled it?
- Was it operational?
- Was it appropriate for the task?
- Did the worker know where it was?
- Did the worker have permission to use it?
- How long would retrieval have taken?
- Was another worker using it?
- Had the worker previously used it?
- Was the worker specifically expected to use it for this assignment?
When Misuse of a Safety Device May Establish the Defense
A worker’s misuse of an otherwise adequate device can support sole proximate cause.
Examples may include:
- standing on the top cap of a ladder despite an available taller ladder;
- using a closed A-frame ladder as a leaning ladder despite a readily available proper device;
- disconnecting a harness from a usable anchorage system;
- positioning a rope grab incorrectly;
- operating a lift contrary to specific training;
- using a bucket, crate, or makeshift platform instead of an available ladder;
- carrying materials by hand when an available rope or hoist was expected to be used.
But misuse does not automatically establish the defense. The defendant must still prove that the equipment, when properly used, would have furnished adequate protection.
Defense Investigation Checklist
The sole proximate cause defense is usually won or lost during the initial investigation.
Secure the equipment
Preserve and photograph:
- ladders;
- scaffolds;
- lifts;
- harnesses;
- lanyards;
- lifelines;
- rope grabs;
- anchor points;
- ropes;
- hoists;
- tie-off systems;
- manufacturer labels;
- inspection tags;
- locking mechanisms;
- footing and surface conditions.
Do not permit critical equipment to disappear, be altered, returned to a rental company, or placed back into service before it is documented.
Identify every alternative safety device
Determine:
- what devices were at the project;
- their precise locations;
- whether they were operational;
- who controlled them;
- whether the worker had used them before;
- whether the worker knew how to access them;
- whether they were assigned to the worker or crew.
Obtain witness statements promptly
Statements should address:
- the assigned task;
- who issued the assignment;
- the expected method;
- safety instructions;
- available devices;
- the worker’s response;
- whether the worker was rushed;
- whether the worker complained about unavailable equipment;
- whether another device was being used;
- whether the worker had performed the task safely before.
Preserve documentary evidence
Collect:
- daily reports;
- toolbox-talk records;
- orientation documents;
- safety manuals;
- job hazard analyses;
- pre-task plans;
- equipment logs;
- inspection records;
- text messages;
- photographs;
- surveillance recordings;
- delivery and rental records;
- disciplinary records concerning prior safety violations;
- OSHA or site-safety reports.
Compare every account of the accident
Review:
- incident reports;
- workers’ compensation forms;
- ambulance records;
- emergency-room histories;
- employer reports;
- recorded statements;
- deposition testimony;
- social-media posts;
- subsequent medical histories.
Inconsistencies may create a factual issue as to whether the safety device moved, failed, collapsed, or played any causal role.
Questions Claims Professionals Should Ask
When evaluating a potential sole proximate cause defense, claims professionals should ask:
- What precise device does the defense contend the worker should have used?
- Where was that device at the time of the accident?
- Was it operational and appropriate for the task?
- How do we know the worker knew it was available?
- How do we know the worker was expected to use it?
- Was there a specific instruction or only a general warning?
- Did the worker have a good reason for not using it?
- Was the worker under time pressure?
- Was the device being used by someone else?
- Did the worker need permission to obtain it?
- Would the device actually have prevented the accident?
- Is there evidence of another statutory failure?
- Does the plaintiff claim the supplied device shifted, failed, or was inadequate?
- Are there photographs or videos?
- Have all relevant witnesses been identified?
Reserve and Settlement Implications
A viable sole proximate cause defense can substantially alter exposure, but it should not be credited merely because the worker acted unsafely.
For reserve purposes, distinguish among four levels of proof.
Strong defense
- a specific adequate device was present;
- the worker knew exactly where it was;
- the worker had used it before;
- the worker was specifically instructed to use it;
- no defect prevented its use;
- witnesses and documents corroborate the instruction;
- proper use would have prevented the accident.
Potential defense with factual disputes
- an adequate device may have been available;
- testimony conflicts about its location or suitability;
- the instruction is disputed;
- the worker claims there was a reason not to use it;
- experts disagree over whether the supplied device was adequate.
Comparative negligence only
- the worker acted carelessly;
- the worker used poor judgment;
- the worker violated a general safety rule;
- the worker failed to ask for assistance;
- no specific alternative device has been identified;
- absent or inadequate protection also contributed to the accident.
Weak defense
- the supplied ladder or scaffold moved or collapsed;
- no alternative device was available;
- no anchorage point existed;
- safety equipment was locked or inaccessible;
- the worker was directed to proceed without protection;
- the defendant cannot identify how the accident could have been prevented using available equipment.
Defense Motion Strategy
A defendant moving for summary judgment should affirmatively establish every element of the defense.
The motion should identify:
- the adequate device;
- its location;
- its condition;
- its suitability;
- the worker’s knowledge;
- the instruction or expectation;
- the absence of a good reason for nonuse;
- the causal connection between nonuse and the accident.
Avoid arguing only that the worker was negligent. That invites the court to characterize the conduct as comparative fault, which is not a defense.
When opposing the plaintiff’s motion, the defense burden is lower: it need only produce admissible evidence creating a material factual dispute. Even so, conclusory affidavits that “all necessary equipment was available” are often inadequate.
A useful affidavit should state:
- the witness’s role and personal knowledge;
- what equipment was present;
- where it was located;
- why it was appropriate;
- what instruction was given;
- when and where the instruction was given;
- whether the worker acknowledged it;
- whether the worker could obtain the device without delay;
- why use of the device would have prevented the accident.
Common Plaintiff Counterarguments
Plaintiffs commonly respond that:
- the device was not actually available;
- the device was too far away;
- another worker was using it;
- the device was defective;
- the worker was never told to use it;
- the worker did not know where it was;
- the task could not be performed using the proposed device;
- the supervisor directed the worker to proceed as he did;
- the alternative method was impractical;
- no anchorage point existed;
- the accident resulted from the supplied device’s movement or failure;
- the employer imposed time pressure;
- the worker’s conduct was merely comparative negligence.
The defense should anticipate these points before depositions, not for the first time during summary-judgment briefing.
Frequently Asked Questions
Is a worker’s negligence a defense under Labor Law § 240(1)?
Ordinary comparative negligence is not a defense. The worker’s conduct defeats liability only when it was the sole proximate cause and no statutory violation contributed to the accident.
Does a worker lose automatically because he ignored an instruction?
No. The instruction should ordinarily concern the use of an adequate, available safety device or a safe method that incorporated adequate protection. A general instruction to avoid danger is not itself a safety device.
Must the safety instruction be given immediately before the accident?
Not necessarily. Cahill recognized that an earlier instruction may be sufficient when the worker knew the equipment was available and understood that he was expected to use it.
Is a ladder located somewhere at the project considered available?
Not automatically. The evidence should establish practical availability, including location, accessibility, suitability, the worker’s knowledge, and authority to use it.
Can misuse of a ladder establish sole proximate cause?
Yes, particularly where an adequate ladder was supplied and the worker chose to use it improperly. But if the ladder shifted, collapsed, was too short, or otherwise failed to provide proper protection, the misuse may be characterized as comparative negligence.
Is failing to have a coworker hold a ladder enough?
Not ordinarily. In Zampko, the Second Department held that the worker’s failure to have another person hold the ladder did not establish nonuse of an available safety device.
Can conflicting accident accounts defeat the plaintiff’s motion?
Yes. Inconsistencies concerning whether a ladder moved, whether the worker fell, or how the injury occurred can create credibility and causation questions, as demonstrated by Delisle.
Who has the burden on summary judgment?
The plaintiff must initially establish a statutory violation and proximate causation. A defendant opposing the motion may raise a factual issue through evidence that adequate protection was available and that the worker’s conduct may have been the sole proximate cause.
A defendant seeking dismissal must establish the defense affirmatively as a matter of law.
Key Takeaways
The sole proximate cause defense is not simply a more forceful version of comparative negligence.
It depends on proof that:
- proper protection was supplied;
- the worker knew about it;
- the worker was expected to use it;
- there was no good reason for failing to do so;
- using it would have prevented the accident; and
- no separate statutory violation contributed to the injury.
The strongest defense record identifies a particular device and connects it directly to the worker, the assignment, the instruction, and the mechanics of the accident.
The weakest record merely establishes that the worker could have acted more carefully.