STANDARD OF CARE

Defining the "Standard of Care": How Expert Witnesses Evaluate Professional Engineering Negligence

Travis Basnett, PE · Licensed in SC, NC & GA · August 2, 2026 · 7-minute read

Professional negligence rarely turns on whether a design was perfect. It turns on the applicable standard of care.

Engineering disputes often begin with a technical question: Did the design, review, or construction-phase service meet the level of care expected of a reasonably prudent engineer?

The answer is rarely found in a single calculation, code section, or project outcome. Engineering relies on mathematics and physical principles, but professional practice also requires judgment. When a project experiences flooding, settlement, pavement failure, cost growth, or delay, the existence of a problem does not by itself establish professional negligence.

Instead, the analysis generally turns on the applicable standard of care, whether the engineer's conduct departed from that standard, and whether any departure contributed to the claimed loss.

This article describes the framework an engineering expert may use to evaluate those questions. The precise legal standard and the testimony required to establish it vary by jurisdiction and by the facts of the matter.

What the Standard of Care Generally Means

The standard of care does not ordinarily require a perfect design, an error-free set of plans, or a project that anticipates every possible condition. It generally asks whether the engineer exercised the level of knowledge, skill, and care that a reasonably prudent member of the profession would have exercised under similar circumstances.

Several parts of that formulation matter:

Reasonably prudent—not perfect. The analysis is based on competent professional practice, not hindsight or an idealized design.
Similar circumstances. Project type, scope, budget, schedule, available information, site conditions, and the engineer's contractual role can all affect the evaluation.
At the relevant time. The engineer's work should be judged using the information, standards, and tools reasonably available when the services were performed.
Within the applicable professional and legal context. Licensing rules, statutes, contractual requirements, and local practice may affect the inquiry.

An unfavorable outcome is evidence to investigate, but it is not the standard itself. A costly change order, for example, may result from an engineering error, an owner-directed change, an unforeseen site condition, incomplete information, construction sequencing, or several contributing factors.

Code Compliance Is Important—but It May Not Resolve the Question

Codes, regulations, permit requirements, and published design standards are important evidence. They may establish mandatory criteria and often provide a useful starting point for evaluating professional conduct.

Compliance alone, however, may not answer every standard-of-care question. A code provision may establish a minimum requirement while the project circumstances call for additional investigation, analysis, coordination, or documentation. Conversely, a difference from a customary practice does not automatically establish negligence if the engineer used a reasonable, technically supported alternative.

An expert may therefore ask:

Which codes and standards applied when the work was performed?
Did the engineer correctly identify and apply them?
Were site-specific risks apparent from the available information?
Did the scope require additional investigation or coordination?
Was the engineering judgment documented and technically supportable?
Did the permitting authority raise concerns, and how were they addressed?

The relevant question is not simply whether a project passed review. It is whether the engineer's work was reasonable under the circumstances.

The Context an Expert Must Reconstruct

Because the standard of care depends on circumstances, a useful evaluation begins by reconstructing the professional environment in which the decisions were made.

1. Timing and Hindsight

Later knowledge should not be imposed on an earlier design without careful analysis. An expert should identify the rainfall data, mapping, codes, software, published guidance, and site information available during the relevant period.

For example, a drainage design prepared years earlier should generally be evaluated using the information and criteria reasonably available at that time. A later extreme event or updated dataset may explain system performance without proving that the original design was unreasonable.

2. Project Type and Site Conditions

The same detail may be appropriate on one project and inadequate on another. The expected investigation and analysis may change with the facility's use, the consequences of failure, soil and groundwater conditions, topography, flood exposure, adjacent development, and other site-specific risks.

3. Scope and Professional Role

The expert must distinguish what the engineer agreed to perform from work assigned to other consultants, contractors, owners, or agencies. Design responsibility, delegated design, construction observation, shop-drawing review, testing, and maintenance are different functions.

A problem outside the engineer's scope does not automatically become the engineer's responsibility. At the same time, a limited scope may not excuse the failure to communicate a material condition that became apparent during the work.

4. Regional and Regulatory Practice

Engineering practice can vary by jurisdiction and setting. Local permitting procedures, agency expectations, geology, climate, and common construction methods may provide relevant context. The weight assigned to locality differs among jurisdictions, so the governing legal standard should be coordinated with counsel.

How the Technical Review Is Conducted

A defensible expert opinion should rest on a transparent method that can be explained and tested. The work commonly includes four related steps.

1. Establish the Project Record

The expert reviews the documents that show what was known, required, designed, communicated, and built. Depending on the matter, those records may include:

Contracts and scopes of service
Surveys, geotechnical reports, and design criteria
Plans, specifications, calculations, and models
Permit records and agency comments
Requests for information, submittals, and change orders
Field reports, testing records, and construction photographs
Emails and other project correspondence
Record drawings, maintenance records, and later surveys

Chronology matters. A document created after the disputed decision may help explain the outcome, but it should not be treated as information the engineer possessed earlier.

2. Perform Independent Technical Analysis

The expert may independently check the disputed work using appropriate calculations, models, measurements, and field observations. In a civil engineering matter, that may include evaluating drainage areas, runoff rates, pipe or channel capacity, grading, elevations, utility geometry, pavement sections, earthwork, or erosion-control measures.

The purpose is not simply to design the project again. It is to test the original assumptions and decisions using a method relevant to the questions in dispute.

3. Compare the Work With Contemporaneous Professional Practice

Codes and calculations are only part of the benchmark. The expert may also consider published standards, technical guidance, customary quality-control procedures, licensing-board materials, and comparable professional practice from the relevant period.

The comparison should be specific. A useful opinion identifies the act or omission being evaluated, the professional expectation that applied, and the evidence supporting the comparison.

4. Separate Standard of Care From Causation and Damages

A departure from the standard of care does not necessarily cause the claimed damage. These are related but distinct questions.

Consider a warehouse floor that cracks and settles. The review might identify an error in a structural or civil detail. Separate investigation might also reveal unsuitable fill, groundwater, construction deficiencies, or an undocumented subsurface condition. The expert must evaluate whether the identified departure actually contributed to the observed failure and whether other causes better explain the condition.

Counsel ultimately addresses the governing legal concepts. The engineering expert's role is to explain the technical causal relationship—and the limits of what the evidence supports.

Communication and Quality Control Are Part of the Evidence

Professional engineering involves more than producing calculations. Coordination, review, and communication may be central to the standard-of-care analysis.

The project record may show:

Whether identified conflicts were resolved
Whether significant assumptions were communicated
Whether changes were incorporated into the plans
Whether calculations and drawings received appropriate quality review
Whether field observations were documented and acted upon
Whether the engineer responded reasonably when new information emerged

Not every missed coordination item is negligence. The significance depends on the engineer's role, the foreseeable consequence, the information available, and the connection to the alleged loss.

What a Useful Expert Opinion Should Accomplish

A well-supported opinion should do more than announce that the work was acceptable or deficient. It should:

Identify the applicable technical question.
State the facts and documents relied upon.
Explain the professional benchmark used.
Compare the engineer's conduct with that benchmark.
Distinguish technical errors from reasonable professional judgment.
Evaluate whether any departure contributed to the claimed condition.
Identify uncertainties, alternative causes, and additional information needed.

This structure makes the opinion easier for counsel, clients, courts, and other experts to evaluate.

The Value of Early Evaluation

Early technical review can help counsel determine whether a disappointing project outcome reflects a potential professional departure, a construction issue, a maintenance problem, an unforeseen condition, or overlapping causes.

It can also identify the records that should be preserved, the measurements that should be taken before conditions change, and the technical questions that should guide discovery.

The standard of care is not a guarantee of perfection. It is a context-dependent measure of reasonable professional conduct. A credible engineering evaluation respects that distinction, applies a transparent methodology, and separates what the evidence demonstrates from what remains uncertain.

Evaluating a potential claim? I provide expert witness support and limited independent technical review for civil engineering disputes involving stormwater, drainage, and site infrastructure.

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About the Author

Travis Basnett, PE is a civil engineer with 16 years of experience in civil site development, stormwater design, drainage evaluation, and flooding investigations. He provides expert witness support and independent technical review for civil engineering disputes and is licensed in South Carolina, North Carolina, and Georgia.

Disclaimer: This article is intended for general informational purposes and does not constitute legal or engineering advice regarding any specific matter. The applicable standard of care and evidentiary requirements vary by jurisdiction and circumstance.