ironclad alibi

Translations
железное алиби
He had an ironclad alibi for the night of the crime.
У него было железное алиби на ночь преступления.
Definitions
An ironclad alibi refers to a strong and indisputable excuse or justification that proves a person was not present at the scene of a crime or wrongdoing, making it impossible for them to have committed the act.
Words
alibi

noun
алиби
ironclad

noun
броненосец