  We consider a normal lead coupled to a Majorana bound state. We show that the
spin-resolved current correlations exhibit unique features which distinguish
Majorana bound states from other low-energy resonances. In particular, the
spin-up and spin-down currents from a Majorana bound state are anti-correlated
at low bias voltages, and become uncorrelated at higher voltages. This behavior
is independent of the exact form of coupling to the lead, and of the direction
of the spin polarization. In contrast, an ordinary low-energy Andreev bound
state gives rise to a positive correlation between the spin-up and spin-down
currents, and this spin-resolved current-current correlation approaches a
non-zero constant at high bias voltages. We discuss experimental setups in
which this effect can be measured.
