  The production of jets in polarized proton collisions at STAR is dominated by
quark-gluon and gluon-gluon scattering processes. The dijet longitudinal
double-spin asymmetry $(A_{LL})$ is sensitive to the helicity distributions and
may be used to extract information about the gluon helicity contribution
$\Delta{g(x,Q^2)}$ to the spin of the proton. Previous STAR jet measurements at
$\sqrt s$ = 200 GeV show evidence of polarized gluons for gluon momentum
fractions above 0.05. The measurement of dijet $A_{LL}$ at $\sqrt s$ = 510 GeV
will extend the current constraints on $\Delta{g(x,Q^2)}$ to lower gluon
momentum fractions and allow for the reconstruction of the partonic kinematics
at leading order. These proceedings present preliminary results from the dijet
$A_{LL}$ measurement from $\sim50 pb^{-1}$ of $\sim50 \%$ polarized proton data
taken during the 2012 RHIC run.
