  We report on a comparison of two possible $\Lambda_c^+$ spin hypotheses,
$J=\frac{1}{2}$ and $\frac{3}{2}$, via the process
$e^+e^-\to\Lambda_c^+\bar\Lambda_c^-$, using the angular distributions of
$\Lambda_c^+$ decays into $pK_S^0$, $\Lambda\pi^+$, $\Sigma^0\pi^+$, and
$\Sigma^+\pi^0$. The data were recorded at $\sqrt s = 4.6$ GeV with the BESIII
detector and correspond to an integrated luminosity of 587 pb$^{-1}$. The
$\Lambda_c^+$ spin is determined to be $J=\frac{1}{2}$, with this value favored
over the $\frac{3}{2}$ hypothesis with a significance corresponding to more
than 6 Gaussian standard deviations.
