Spectroscopy of the high-lying vibrational levels of the 1\sp3Σ\sbspg+ and 1\sp1Σ\sbspu+ states of both \sp6Li\sb2 and \sp7Li\sb2 has been accomplished via photoassociation of ultracold atomic lithium confined in a magneto-optical trap. Both these molecular states correlate to 2S\sb1/2 plus 2P\sb1/2 free atomic states. The long range part of these molecular potentials depends on the 2P atomic radiative lifetime. Accurate models were constructed for both the 1\sp3Σ\sbspg+ and 1\sp1Σ\sbspu+ potentials. By fitting these models to the experimentally measured vibrational levels observed in \sp6Li\sb2 and \sp7Li\sb2, we have been able to extract a value for the 2P lifetime of lithium. Fitting to the absolute values of the data gives a value of 26.99 ± 0.16 ns whereas fitting to differences in the spectral features gives a value of 27.04 ± 0.18 ns. While both values agree with previous work, improvements made in the potential models would enable this analysis to resolve the current discrepancy between experiment and theory.