In pari materia meaning

In pari materia describes treating two or more enactments or provisions as dealing with the same subject matter, so they should be read together when interpreting the law. It is a descriptive Latin maxim used in statutory interpretation rather than a term defined by legislation; its operation is developed through case law and legal commentary. Courts use it to harmonise language, resolve ambiguity and promote coherent construction across cognate legislation—commonly where statutes form part of a scheme, are consolidations, or contain successive amendments. The presumption is that related provisions use words consistently and pursue a consistent purpose. It does not permit departure from clear statutory text, nor the importation of words that are not there; there must be a genuine overlap in subject matter and legislative intent. Usage is broadly consistent across England and Wales, Scotland, Northern Ireland and Ireland. It may apply within a single Act, between Acts, or between primary and secondary legislation, and can extend to devolved or EU‑derived measures that cover the same field. Practitioners invoke it to argue for consistency of meaning across related statutes unless Parliament or the Oireachtas has indicated a contrary intention.