That one can believe that abortion is wrong and still be pro-choice. I believe that suicide is wrong in most cases (hurts your family and friends--a lot), but I don't think it should be *illegal*. Similarily, you can think that something is *wrong*, but shouldn't necessarily be illegal, because the purpose of laws is to create a smoothly-running society with a minimum of interpersonal harm, not a "moral" society. If he were pro-choice in a Catholic *theocracy*, your point would make sense.
I'm going camping with my family for a couple days so I cannot discuss this point very long but... In the Catholic view point Abortion is the murder of an inocent life, and any lawmakers who vote in suport of this practice (yes including votes to keep it legal) are condoning the act.
If say we substituted the terminating of the life of "blondes" (all ages) for "Fetuses" (Babies) and Law makers were voting in favor of legalizing it would the view of 'keeping it "legal" while beliveing it is "wrong" yourself' hold water?
From the Catholic viewpoint there is no real difference between those two situations, (except maybe that some of the blondes had a chance to defend themselves) both are wrong.
"Anybody who goes to bed the same day they got up is a quitter."
Achewon Nutiket*
*Spiritual Guard
† RIP Kory †