  Topological charge screening has been proposed as the mechanism responsible
for the anomalous suppression in the first moment of the polarized proton
structure function -- the `proton spin' effect. An immediate consequence is
that this suppression should be target-independent, since the screening is a
fundamental property of the QCD vacuum. Here, we study the possibility of
testing the target-independent suppression in semi-inclusive target
fragmentation processes at polarized HERA.
