  We investigate the potential for searching and identifying the leptoquark
(LQ) effects in the charm sector through the low-energy polarized scattering
processes $\vec{e}^{\,-}p\to e^-\Lambda_c$, $e^-\vec{p}\to e^-\Lambda_c$, and
$\vec{e}^{\,-}\vec{p}\to e^-\Lambda_c$. Considering only the longitudinally
polarized processes, we show that the different LQ models can be disentangled
from each other by measuring the four spin asymmetries, $A_{L}^e$, $A_{L}^p$,
$A_{L3}^{ep}$, and $A_{L6}^{ep}$, constructed in terms of the polarized cross
sections. Although it is challenging to accomplish the same goal with
transversely polarized processes, we find that investing them in future
experiments is especially beneficial, since they can directly probe into the
imaginary part of the Wilson coefficients in the general low-energy effective
Lagrangian. With our properly designed experimental setups, it is also
demonstrated that promising event rates can be expected for all these processes
and, even in the worst-case scenario -- no LQ signals are observed at all, they
can still provide a competitive potential for constraining the new physics,
compared with those from the conventional charmed-hadron weak decays and the
high-$p_T$ dilepton invariant mass tails at high-energy colliders.
