  Sulfur abundances have been determined for ten stars to resolve a debate in
the literature on the Galactic chemical evolution of sulfur in the halo phase
of the Milky Way. Our analysis is based on observations of the S I lines at
9212.9, 9228.1, and 9237.5 A for stars for which the S abundance was obtained
previously from much weaker S I lines at 8694.0 and 8694.6 A. In contrast to
the previous results showing [S/Fe] to rise steadily with decreasing [Fe/H],
our results show that [S/Fe] is approximately constant for metal-poor stars
([Fe/H] < -1) at [S/Fe] = +0.3. Thus, sulfur behaves in a similar way to the
other alpha elements, with an approximately constant [S/Fe] for metallicities
lower than [Fe/H] = -1. We suggest that the reason for the earlier claims of a
rise of [S/Fe] is partly due to the use of the weak S I 8694.0 and 8694.6 A
lines and partly uncertainties in the determination of the metallicity when
using Fe I lines. The S I 9212.9, 9228.1, and 9237.5 A lines are preferred for
an abundance analysis of sulfur for metal-poor stars.
