Forensic Science and Criminalistics

The application of scientific principles and methods to questions arising in legal investigations and proceedings.

The scientific examination and interpretation of physical evidence associated with criminal investigations.

To provide scientifically supported information relevant to legal questions without favoring either party.

A systematic process involving observation, hypothesis formulation, testing, analysis, and evaluation of conclusions.

A proposed explanation that can be evaluated through observation, testing, or other reliable evidence.

The principle that a scientific claim must be capable of being challenged or disproved by relevant evidence.

The ability to obtain consistent results through appropriate repetition of an examination or analysis under specified conditions.

The consistency of results obtained when the same method is applied under substantially the same conditions.

A quantitative expression of the range or dispersion of values reasonably attributable to a measured quantity.

The closeness of a measurement result to an accepted reference or true value.

The closeness of repeated measurement results to one another.

Yes. Repeated results may closely agree while remaining systematically different from the true value.

A consistent or predictable deviation that shifts results away from the correct value.

Unpredictable variation that causes repeated measurements to differ.

The process of establishing that an analytical method is suitable for its intended purpose and performs adequately.

The process of confirming that a laboratory can achieve specified performance requirements when using an established method.

A documented set of instructions intended to ensure consistent performance of a particular laboratory activity.

Planned and systematic activities intended to provide confidence that laboratory processes and results meet established requirements.

Operational checks used to monitor whether an analytical process is functioning as intended.

A sample expected to produce a positive result, used to check whether a test can detect its intended target.

A sample expected to produce a negative result, used to identify contamination or unwanted reactions.

A control containing analytical reagents without the questioned sample, used to detect contamination introduced by reagents or processing.

A material with sufficiently established properties used for calibration, quality control, or method assessment.

A reference material accompanied by authoritative documentation specifying certified property values and associated information.

The establishment of a relationship between an instrument's indications and known reference values.

It supports measurement accuracy, traceability, and reliable interpretation.

The property of a measurement result being related to a reference through a documented, unbroken chain of calibrations, each contributing to uncertainty.

An assessment of laboratory or examiner performance using test materials or exercises with independently evaluated outcomes.

The evaluation of measurements or test results produced by two or more laboratories using comparable materials.

Formal recognition by an accreditation body that a laboratory meets specified competence and management requirements within an identified scope.

An international standard specifying general requirements for the competence, impartiality, and consistent operation of testing and calibration laboratories.

No. Accreditation supports demonstrated systems and competence but does not eliminate errors or uncertainty.

The requirement that examinations and conclusions remain objective and free from improper influence.

The influence of irrelevant background information on an examiner's observations, judgments, or conclusions.

An independent review performed without disclosure of the original examiner's conclusion, when feasible under the procedure.

An observation or measurement produced through examination of submitted evidence.

The evaluation of analytical findings in relation to relevant propositions, context, and scientific limitations.

An analytical result describes findings; an expert conclusion explains their significance using specialized knowledge and reasoning.

The probability of observing the evidence under one proposition divided by its probability under an alternative proposition.

No. It compares the probability of the evidence under specified propositions, not the probability of guilt.

The error of treating the probability of evidence given innocence as though it were the probability of innocence given the evidence.

The error of dismissing evidence because a characteristic may occur in other people without properly considering its evidential value.

A conclusion that the evidence is inconsistent with a proposed source or association under the applicable examination criteria.

A result that does not provide sufficient support for either a specified association or an exclusion.

To evaluate the technical adequacy, reasoning, documentation, or conclusions of work performed by another examiner.

An assessment of the scientific content, analytical records, calculations, and conclusions for accuracy and compliance with requirements.

A check of documentation, identifiers, completeness, formatting, and procedural compliance.

To explain relevant specialized methods, findings, interpretations, and limitations to the court.

The measurements may be precise but inaccurate, suggesting systematic error or another analytical problem.

Investigate possible contamination or test failure and assess the validity of affected results before reporting them.