Both of my parents are SJ, and generally liberal (liberal for federal government, conservative for municipal, liberal in general).
Both of my parents seem to say all the liberal things (in terms of the real liberal ideas of people being able to do what they want) and beleive them, yet they still contradict them without realizing it. For example, if you ask my dad (ESTJ) what he thinks about rights he'll probably say everyone should have the right to do what they want, and he does think that, but then when someone (even his own children
) does soemthing unorthodox he'll notice and point it out. When he found out I frequently go running at midnight (he found it very strange) he looked at me very strangely and made me feel like a frea for like ten seconds. Same deal with my habit of making traditionally dinner dishes for breakfast. My mom (ISFJ) is the same. Although they beleive in the freedom everyone inherently has, they still have socialized ideas of how people should behave and react when something goes outside these ideas. My mom's side of the family is especially like this. They are very much the quintessential SJ family, really.
As someone said, I think it's really lifestyle that is conservative rather than politics. My dad has a very SJ lifestyle -golfing and fine wine, and some SJish values (like thinking anyone exposing their body must have issues
). They also have very superstituos socialized beleifs that don't always seem based in reality, but rather social mores, like that there must be murderers out at night (in a quiet suburban neighborhood like mine there is NO ONE out at night). My mom is the same, possibly more so.