The phrase "legal rationale" means the reasoning or explanation behind a legal decision or argument. It refers to the logic and principles used by judges or lawyers to support their interpretation of the law. Full definition
If your claim is denied, you will have to present medical evidence, expert opinions, and legal rationale about why your claim should be approved. (catesmahoney.com)
While the president has persistently argued for steel and aluminum tariffs as a way to create jobs in beleaguered American industries, the formal legal rationale for the measures is actually national security. (vox.com)
However, whilst being able to rely on the Judgment of Keehan J for comfort, they will find that it provides virtually nothing by way of legal rationale. (ukhumanrightsblog.com)