This document summarizes a study that measured the binding energy of negative gallium ions using infrared photodetachment threshold spectroscopy. The experiment involved generating gallium ions using a cesium sputter source, mass selecting them with a magnetic field, and scanning a tunable laser across photon energy thresholds to photodetach electrons. Precise measurements of three photodetachment thresholds were obtained and agreed with theoretical values but revised a previous experimental measurement. A simulation of the experimental data using Wigner's threshold law for photodetachment cross sections also showed good agreement.