Proportionality
Definition
The legal principle, central to European human rights law and to many constitutional systems, that any interference with a fundamental right must be no greater than necessary to achieve a legitimate aim. In DNA law, it governs who may be profiled, for how long, and for what category of offence.
- Legal domain
- Human rights and constitutional law
- Core test
- Interference with a right must not exceed what is necessary for its aim
- Forensic application
- Governs DNA database retention, sampling scope, offence category
- Key instrument
- European Convention on Human Rights, Article 8, in the EU/UK
Common questions
How does proportionality limit DNA database retention?+
Courts have required that indefinite retention of DNA profiles from people never convicted of an offence be time-limited or removed, since keeping the profile indefinitely goes beyond what is necessary for crime prevention. Retention rules therefore vary by conviction status and offence severity.
Does proportionality apply the same way in every jurisdiction?+
No. Countries with a written proportionality test in their constitutional or human rights framework, such as EU member states, apply it as a formal legal standard, while jurisdictions without that doctrine rely on statutory limits or judicial discretion to achieve a similar restraint.
How does proportionality affect the scope of a forensic search?+
It requires that the intrusiveness of a search or sampling method, such as a familial DNA search sweeping in relatives, be justified by the seriousness of the offence being investigated rather than applied routinely to minor crimes.
Related terms
- Chain of Custody
- The documented chronological record of who collected, handled, transferred, and examined a piece of evidence. For digital evidence, chain of custody includes...
- Bharatiya Sakshya Adhiniyam 2023 (BSA)
- India's current evidence statute, which replaced the Indian Evidence Act 1872. Section 63 of the BSA governs electronic records and requires a...
- Breach Notification
- The legal obligation to inform regulators and affected individuals when personal data is compromised in a security incident. Timelines and thresholds differ...
- CODIS
- The FBI's Combined DNA Index System, the US national STR-based forensic DNA database. Contains profiles from convicted offenders, arrestees, and unidentified crime-scene...
- Cold Hit
- A database match between a crime-scene DNA profile and an offender or arrestee profile where no other investigative lead identified the suspect....
- Communicative Theory
- Antony Duff's account of punishment as a message addressed to the offender, calling them to answer for the wrong and to reconcile...
- Denunciation
- The communicative function of punishment: the sentence expresses the community's collective moral condemnation of the act. Rooted in Durkheim's argument that punishment...
- Deterrence
- A forward-looking aim holding that the threat or experience of punishment discourages future offending. General deterrence targets potential offenders in the population;...
- Dwell Time
- The period between an attacker gaining initial access and their detection. Reducing dwell time is a primary goal of threat hunting. The...
- Exculpatory Evidence
- Evidence that tends to clear a suspect of guilt. Investigators have a professional and, in many jurisdictions, a legal duty to document...
- Familial Searching
- The deliberate use of partial DNA profile matches in a forensic database to identify biological relatives of an unknown contributor, on the...
- Forensic Readiness
- The organisational state in which people, processes, and technology are prepared to collect and preserve digital evidence with minimum disruption to business...
Explained in these topics
- The Aims of PunishmentThe principle that punishment should be commensurate with the gravity of the offence. Central to retributive theory and embedded in sentencing law across most...
- DNA Evidence: Legislation, Databases and Privacy
- Incident Response Goals and PrinciplesThe IR principle that the severity of the response must be calibrated to the severity and scope of the incident. A disproportionate response causes unnecessary...
- Legal and Ethical Foundations of Cyber InvestigationsAn ethical and legal principle requiring that the intrusion caused by an investigative action be no greater than necessary to achieve the legitimate aim. Propo...
- Philosophical Theories of PunishmentThe requirement that the severity of a punishment track the seriousness of the offence and the offender's culpability, used as both a retributivist demand and...