Is collecting a percentage as a fine when a check bounces due to insufficient funds considered a usurious transaction, whether the percentage is fixed or increases with the duration of the delay?

A check is a debt instrument, and it is not permissible to impose a fine on the debtor if the check is not cashed due to insufficient funds, because that is blatant usury (riba), whether the fine is a percentage or a fixed amount, and whether it increases with the extension of the term or is imposed once. It is stated in Fatḥ al-ʿAlī al-Mālik that this commitment is void because it is blatant usury.