Definition
Restraining powers are restrictions or limitations placed by a donor upon the exercise of a power that the donor has granted to another. The concept belongs to the law of powers — the body of doctrine governing grants of authority to act with respect to property or legal interests on behalf of, or in place of, the donor. When a donor creates a power (such as a power of appointment, a power of sale, or a fiduciary power over a trust), the donor may simultaneously impose conditions, boundaries, or prohibitions that narrow how, when, or for whose benefit that power may be exercised. Those limiting conditions are the restraining powers.
The term operates within the law of property and trusts more than in any other context. A grantor conveying land might grant a trustee the power to sell, but restrain that power by requiring consent of a beneficiary, limiting sale to particular buyers, or prohibiting sale before a stated date. Each such restriction is a restraining power as to the power of sale.
---
Common Confusion
"Restraining powers" is not synonymous with a restraining order. A restraining order is a court-issued directive compelling or prohibiting conduct by a party in litigation. Restraining powers, by contrast, are private, donor-imposed limitations baked into the original instrument of grant — not a judicial remedy. Researchers encountering "restraining" language in older property and trust instruments should resist the instinct to read it through the lens of injunctive relief.
The term also should not be confused with the broader phrase "power of restraint," which can appear in constitutional and administrative law contexts to describe governmental authority to restrict individual conduct. That usage is analytically distinct.
---
Why It Matters in Research
The chief research challenge with restraining powers is that the concept is embedded in the law of powers generally, and historical sources rarely treat restraining powers as a freestanding doctrine. Researchers must trace them through the instrument creating the power — deed, will, trust agreement, or settlement — rather than through standalone doctrine.
In equity and trust law, the enforceability of a restraining power often turned on whether the restriction was repugnant to the grant itself. A power granted in absolute terms could not, in older equity doctrine, be effectively restrained by a simultaneous condition that contradicted the nature of the grant. This tension — grant versus restraint — generated substantial chancery litigation and is worth watching for when reading 18th- and 19th-century equity reports.
The corpus researcher should also note that "restraining powers" surfaces in the context of powers of appointment, where donor-imposed limitations interacted with the Rule Against Perpetuities and the doctrine of illusory appointments. Tracing the restraining power in a settlement deed may be necessary to determine whether an exercise of a power of appointment was valid.
In constitutional research, a different but related concept appears: congressional or legislative restraints on delegated powers. While doctrinally separate from private restraining powers, the structural logic — a grantor of authority imposing limits on its exercise — runs parallel, and encyclopedia connections to enumerated powers doctrine are worth consulting when the research context shifts to public law.
Finally, OCR degradation in older digitized sources may render "restraining powers" as "restricting powers" or fragment the phrase entirely. Both Black's editions show minor transcription artifacts in the source text, a caution that applies to period instruments and reporters as well.
---
Historical Dictionary Support
Both Black's Law Dictionary and the Second Edition Supplement define restraining powers in identical substantive terms: restrictions or limitations imposed upon the exercise of a power by the donor thereof. The agreement across editions is notable for its brevity — neither entry expands into doctrine, examples, or the interaction of restraining powers with equity's repugnancy rule.
This compression reflects how these dictionaries treated the law of powers generally: as a specialty of property and equity practice that readers were expected to pursue through treatises (Sugden on Powers being the canonical 19th-century authority) rather than through dictionary exposition. What the entries do confirm is that the donor's role is definitional — restraining powers originate with the creator of the power, not with courts or statute. This donor-centric framing distinguishes the concept from judicial and legislative restraints on authority, which occupy different doctrinal space.
Neither edition addresses what happens when a restraining power conflicts with the substantive breadth of the grant, nor do they treat the question of whether restraining powers run with the instrument or may be waived. Researchers needing that doctrinal depth must look beyond these sources.
---
Encyclopedia Cross-Reference
The Law Mind Remedies & Equity Encyclopedia — "Prohibition — Restraining Inferior Courts and Tribunals from Exceeding Jurisdiction": relevant for understanding the judicial counterpart to private restraining powers; the structural parallel between court-imposed jurisdictional restraints and donor-imposed power restraints illuminates both concepts.
The Law Mind Constitutional Law Encyclopedia — "Congressional Power — Enumerated Powers and the Necessary and Proper Clause": relevant when restraining powers analysis extends into public law, particularly where a delegating authority imposes express limits on granted legislative or administrative power.
---