Where does negligence collide?

Conduct that falls below the standard established by law for the protection of others against unreasonable risk of harm, in the Restatement (Second) of Torts' 1965 formula at §282, and a cause of action when that conduct causes injury to a person the duty protects. Judge Hand gave the breach question an arithmetic form in Carroll Towing in 1947: an actor is negligent when the burden of precaution is less than the probability of loss multiplied by its gravity. Posner argued in 1972 that nineteenth-century courts had been applying that test all along and that the negligence system's function was to induce efficient care. The construct is a relation between conduct and a standard, not a state of mind, and the defendant's actual awareness is irrelevant to it.[1][2][3]

Unit

A defendant's conduct measured against the reasonable person under like circumstances

Recovery means

Compensatory damages that put the plaintiff in the position they would have occupied

Measured by

Fact-finder's verdict on breach and causation; the Hand formula as a court's articulation, rarely computed

The lowest of the Model Penal Code's four culpability levels, and the only one the actor need not be aware of. Under §2.02(2)(d), drafted in 1962, a person acts negligently when they should be aware of a substantial and unjustifiable risk that an element exists or will result, and the failure to perceive it is a gross deviation from the standard of care a reasonable person would observe in the actor's situation. The gross-deviation clause is what separates this from the tort construct: ordinary carelessness that would lose a civil suit is not a crime. The Code's default rule makes recklessness the floor when a statute is silent, so negligence must be named to apply, and it grounds a small set of offences such as negligent homicide.[4]

Unit

A defendant's failure to perceive a risk, as to each element of an offence

Recovery means

Not applicable, the question is guilt

Measured by

Proof beyond reasonable doubt that the deviation from reasonable care was gross

Care that falls below the standard expected of an average practitioner in the same specialty, as judged by physician reviewers reading the record. The Harvard Medical Practice Study fixed the operational form in 1991: Brennan and colleagues reviewed 30,121 New York hospital records and found adverse events in 3.7 percent of admissions, of which 27.6 percent were attributed to negligence on a six-point confidence scale. Localio and colleagues then matched those records to malpractice claims and found that few negligent injuries produced a claim and that most claims did not correspond to a negligent injury. Negligence here is an epidemiological variable with a measured reviewer agreement, and the study's lasting finding is that it and the legal construct pick out different patients.[5][6]

Unit

An injury caused by medical management and attributed by reviewers to substandard care

Recovery means

Patient recovery from the injury; for the system, a fall in the negligent adverse event rate

Measured by

Structured implicit review by two physicians on a confidence scale; kappa for inter-rater agreement

A category the field declines to use. Reason's 1990 taxonomy divides unsafe acts into errors (slips and lapses in execution, mistakes in planning) and violations, which are deliberate departures from rules, and it locates most accidents in latent conditions upstream of the person at the sharp end. His 2000 paper contrasted the person approach, which blames forgetfulness and carelessness, with the system approach, which treats error as a consequence of how work is designed and defends in depth against holes that momentarily line up. Negligence in the legal meaning belongs to the person approach, and Reason's argument is that it explains little and prevents less. The construct closest to it here is the violation, which is chosen, while errors are not.[7][8]

Unit

An unsafe act classified by its cognitive origin, within a system of defences

Recovery means

Restored defences and redesigned conditions, not a corrected individual

Measured by

Incident reporting and root-cause analysis; error type frequencies by task

The liability rule that gives injurers an incentive to take precaution up to the point where its cost equals the accident cost it avoids. Calabresi's 1970 book set the goal (minimise the sum of accident costs and the costs of avoiding them) and proposed assigning loss to the cheapest cost avoider. Brown formalised the comparison of rules in 1973, and Shavell's 1987 treatise carried the result: a negligence rule with due care fixed at the efficient level induces efficient care by both parties, but leaves the injurer's level of activity unregulated, which strict liability does not. Negligence here is a policy instrument with a comparative statics, and the standard of care is chosen to make the marginal precaution just worth taking.[9][10][11]

Unit

A liability rule and the care and activity levels it induces

Recovery means

Not applicable, the criterion is minimised total accident cost

Measured by

Model comparisons of care and activity under alternative rules; empirical tests on accident rates after rule changes