four corners

plural plural-only

(law) The face of a document or its contents, considered without reference to any outside information.

Japanese Meaning

文書の表面、つまり記載内容そのもの（外部情報を考慮せず文書内部のみに基づく解釈）。 / 法的な文脈では、文書自体の記述だけに基づいて判断するという原則を示す。

The court examined the contract within its four corners and found no ambiguity.

裁判所は書類の文言の範囲内で契約書を検討し、曖昧さはないと判断した。

Sense（1）

(law) The face of a document or its contents, considered without reference to any outside information.

If Republicans don't think it's a coup or doesn't fit this definition of a coup in all four corners then I'd love to hear what they would call it.