The different roles of case law in civil and common law traditions create differences in the way that courts render decisions. Common law courts generally explain in detail the legal rationale behind their decisions, with citations of both legislation and previous relevant judgments, and often interpret the wider legal principles. The necessary analysis (called ratio decidendi), then constitutes a precedent binding on other courts; further analyses not strictly necessary to the determination of the current case are called obiter dicta, which constitute persuasive authority but are not technically binding.