For a Catholic, supporting abortion by knowingly voting for it is "formal cooperation"[1] with the taking of innocent human being's lives. This is why by Canon

For a Catholic, supporting abortion by knowingly voting for it is "formal cooperation"[1] with the taking of innocent human being's lives. This is why by Canon law, not that it's always followed, politicians who support abortion should not be given communion: they are manifestly in a state of mortal sin and giving them communion is desecrating the Eucharist and causing scandal[2]. Because of this, well catechized Catholics will oppose abortion. That said, it's unproductive to be a jerk about it and the correct response for those who don't have pastoral responsibility for the individuals in question is just to pray that they realize their error and repent. [1] https://www.consciencelaws.org/religion/religion002.aspx https://www.consciencelaws.org/religion/religion002.aspx [2] In this context, by scandal Catholics mean action that invites others to sin.