Use ～手前 in reports, negotiations, or internal discussions to explain that, having said or done something publicly, you cannot now back out without losing face. It frames an obligation that comes from appearances and social position rather than from rules or logic, and is nearly always followed by a negative-possibility ending such as ～わけにはいかない・～できない・～しかない. Distinguish it from 以上（は）, which stresses logical commitment, and from ～からには, which lacks the face-saving nuance.