Legal Definitions - de facto law

De facto law refers to a practice, rule, or formality that is followed and enforced in reality, even if it is not officially written down, formally enacted, or legally recognized as a statute or regulation. The term "de facto" means "in fact" or "in reality," distinguishing it from "de jure," which means "by law." Therefore, a de facto law is something that operates as law in practice, rather than by formal legal decree.

• Example 1: Unwritten Agency Procedures

  Imagine a state environmental protection agency that, for years, has consistently required all new industrial facilities to submit a detailed "community impact report" before their permits are approved. This requirement is not explicitly stated in the agency's official regulations or state statutes. However, every applicant knows that failing to submit such a report will lead to significant delays or outright rejection of their permit application.

  This scenario illustrates a de facto law because the requirement for a community impact report functions as a mandatory rule in practice, dictating the behavior of applicants and the agency's decision-making, even though it lacks formal legal codification.

• Example 2: Neighborhood Custom

  Consider a residential community where, for decades, residents have maintained an unwritten understanding that all household trash must be placed in sealed, animal-proof containers at the curb, despite the city's official sanitation rules only requiring trash to be bagged. If a new resident places loose bags of trash out, they quickly receive polite but firm requests from neighbors to use proper containers, often citing concerns about pests and aesthetics.

  Here, the practice of using sealed, animal-proof containers acts as a de facto law. It's a widely accepted and enforced community standard that governs waste disposal behavior, even though it's not a formal city ordinance or homeowners' association rule.

• Example 3: Industry Standard as a Guideline

  In the software development industry, many companies adhere to a "best practice" of conducting extensive security audits on all new products before release, even if the specific type and frequency of these audits are not mandated by any government regulation or contractual obligation. Companies that skip these audits often face reputational damage or increased liability if a security breach occurs, making the audits a practical necessity for market acceptance and trust.

  This industry-wide practice of rigorous security audits functions as a de facto law. While not a formal legal requirement, it is a deeply embedded expectation that effectively dictates how software products are developed and released, influencing business conduct as if it were a binding regulation.