Social Justice isn't a farther than left policy, I was taught it by a far-right conservative Catholic, it's actually supported by the Vatican.
The Catholic Church can't really be placed on a "left-right" axis -- they have a lot of "left-wing" views on money combined with a lot of "right-wing" views on what you should be allowed to do with your penis.
I've always thought of "social justice" as a left-wing buzzword rather than an actual policy.