  The background field method is used to linearize the Weyl invariant
scalar-tensor gravity, coupled with a Stueckelberg field. For a generic
background metric, this action is found to be not invariant, under both
diffeomorphism and generalized Weyl symmetry, the latter being a combination of
gauge and Weyl transformations. Interestingly, the quadratic Lagrangian,
emerging from a background of Minkowski metric, respects both the
transformations, independently. Becchi-Rouet-Stora-Tyutin (BRST) symmetry of
scalar-tensor gravity coupled with a Stueckelberg-like massive gauge particle,
possessing diffeomorphism and generalized Weyl symmetry, reveals that in both
the cases, negative norm states with unphysical degrees of freedom do exist. We
then show that, by combining diffeomorphism and generalized Weyl symmetries,
all the ghost states decouple, thereby removing the unphysical redundancies of
the theory. During this process, the scalar field does not represent any
dynamic mode, yet modifies the usual harmonic gauge condition through
non-minimal coupling with gravity.
