When a leading stimulus is followed shortly thereafter by another similar stimulus coming from a different direction, listeners often report hearing a single auditory event at or near the location of the leading stimulus. This is called the precedence effect (PE). We measured masked detection thresholds for a noise target in the presence of a masker composed of (1) a lead/lag noise pair with the lead ITD set the same or opposite to the target, (2) a diotic masker, and (3) a dichotic pair of decorrelated noises. If the PE results in actual elimination of the lag stimulus, we would expect lower masked thresholds when the lead ITD is opposite to that of the target, as predicted by spatial release from masking. Results show that for small lead/lag delays, detection thresholds were similar to those for the diotic masker, regardless of whether the lead ITD was the same or opposite to that of the target. For longer lead/lag delays, which are unlikely to elicit the PE, thresholds approached those measured for dichotic maskers composed of two decorrelated noises. An extended EC model is used to simulate the psychophysical results. [Work supported by NSF BCS-1539276 and NSF BCS-1539376.]