  We give a theory of the inverse spin Hall effect (ISHE) in ferromagnetic
metals based on skew scattering via collective spin fluctuations. This extends
Kondo's theory of the anomalous Hall effect (AHE) to include short-range
spin-spin correlations. We find a relation between the ISHE and the four-spin
correlations near the Curie temperature TC. Such four-spin correlations do not
contribute to the AHE, which relates to the three-spin correlations. Thus our
theory shows an essential difference between the AHE and ISHE, providing an
essential complement to Kondo's classic theory of the AHE in metals. We note
the relation to skew-scattering mechanisms based on impurity scattering. Our
theory can be compared to recent experimental results byWei et al. [Nat.
Commun. 3, 1058 (2012)] for the ISHE in ferromagnetic alloys.
