A low‐pressure mercury‐argon discharge is probed with a new technique of laser spectroscopy to determine the influence of the Hg(63P2) population on discharge emission. The discharge is excited with inductively coupled rf power. Variations in the intensity of emission lines in the discharge were examined as &lgr;=546.1 nm light from a cw laser excited the Hg 63P2‐to‐73S1transition. The spectrum of the discharge viewed in the region of laser irradiation showed increased emission in &lgr;=546.1, 435.8, 404.7, 253.7, and 194.2 nm lines. Other lines in Hgiexhibited a decrease in emission. When the discharge was viewed outside the region of laser irradiation, all lines exhibited an increased emission. Based on these results we conclude that the dominant mechanism for the excitation of higher lying levels of mercury is the two‐step electron impact excitation via the3P2level. The depopulation of the metastable level is also responsible for the observed increase in the electron temperature when the laser irradiates the discharge. We also conclude that the3P2metastable level of mercury does not play a significant role in the excitation of the2P1/2level of mercury ion.