  We establish an experimental method for a detailed investigation of inelastic
collisional properties between ytterbium (Yb) in the metastable
${}^3\mathrm{P}_2$ state and ground state lithium (Li). By combining an optical
lattice and a direct excitation to the ${}^3\mathrm{P}_2$ state we achieve high
selectivity on the collisional partners. Using this method we determine
inelastic loss coefficients in collisions between
$^{174}$Yb(${}^3\mathrm{P}_2$) with magnetic sublevels of $m_J=0$ and $-2$ and
ground state $^6$Li to be $(4.4\pm0.3)\times10^{-11}~\mathrm{cm}^3/\mathrm{s}$
and $(4.7\pm0.8)\times10^{-11}~\mathrm{cm}^3/\mathrm{s}$, respectively. Absence
of spin changing processes in Yb(${}^3\mathrm{P}_2$)-Li inelastic collisions at
low magnetic fields is confirmed by inelastic loss measurements on the $m_J=0$
state. We also demonstrate that our method allows us to look into loss
processes in few-body systems separately.
