  While the excess in cosmic-ray electrons and positrons reported by PAMELA and
Fermi may be explained by dark matter decaying primarily into charged leptons,
this does not necessarily mean that dark matter should not have any hadronic
decay modes. In order to quantify the allowed hadronic activities, we derive
constraints on the decay rates of dark matter into WW, ZZ, hh, qqbar and gg
using the Fermi and HESS gamma-ray data. We also derive gamma-ray constraints
on the leptonic e+e-, mu+mu- and tau+tau- final states. We find that dark
matter must decay primarily into mu+mu- or tau+tau- in order to simultaneously
explain the reported excess and meet all gamma-ray constraints.
