The Lightspeed Rule

Before faster-than-light travel, efforts to establish law across inhabited worlds were limited by distance. News of a law or legal precedent could take years to reach affected colonies. By the time a ruling arrived, technology, politics, or facts on the ground might already have changed. More isolated colonies often ignored interstellar law entirely.

The Rule

The lightspeed rule emerged from this chaos. It stated that laws propagate at the speed of light: if a law passed on Earth went into effect immediately, it would not take effect on Sirius Prime until 8.6 years later.

Judicial Precedent

Legal precedents were more complicated. A judicial interpretation might be treated as valid even in places where no one could yet have known about it, creating a messy and often unfair distinction between enacted law and interpreted law.

Purpose and Interpretation

The lightspeed rule was less a coherent philosophy than an emergency doctrine for preserving notice and fairness. It recognized that no person could obey a law they had no physical means of learning. Different jurisdictions implemented it differently, creating disputes over whether the relevant delay began at enactment, publication, transmission, or receipt.

Legal Arbitrage

The rule also encouraged legal arbitrage. Ships could leave a system before unfavorable legislation arrived elsewhere, while corporations maintained relay networks that gave them earlier notice than ordinary settlers. Information speed became a form of privilege even before FTL.

Survival After FTL

After faster travel emerged, the doctrine survived in fragments because old contracts and precedents still referenced it. Courts then had to decide whether a rule designed for unavoidable delay still applied when faster communication was possible but expensive or selectively available.