Morality can be split into two different classes:
1) consequential morality, like murder, burglary...acts with non-consenting human victims...this is the traditional jurisdiction of both the Church and the State; and
2) non-consequential morality, on the other hand, relates to acts which may be sinful or self-detrimental, but have no non-consenting human victims...this is the proper jurisdicton of the Church, but not necessarily the State.
Because the Church only uses persuasion to convince people to act a certain way, the Church can speak to all aspects of morality, both consequential and non-consequential. Thus, as a Catholic, I may believe that it is wrong to use non-abortive birth control like a condom (really, conception control, so no victim is present) and it is wrong to use abortive birth control (post-conception birth control, so a victim is present). But, I don't impose the non-consequential morality on others using the power of the State.
Because the State primarily uses power to convince people to act a certain way (e.g., uses fines and jail time), the State is properly limited to only consequential morality (prevention of victims). Thus, I believe is it proper that the State should stop people from killing other people. This is not purely a religious belief because it is consequential morality. Even atheists support the State addressing consequential morality in general (e.g., anti-murder laws, anti-burglary laws, etc.).
I believe in separation of Church and State, so in general I do not support the State moving into non-consequential morality issues. I leave that stuff to personal belief. Note, however, that I do feel it is legitimate for an individual (or elected representative) to use religious reasoning when voting for instances in which the State tries to encourage or subsidize non-victimizing but religiously wrong behavior through persuasion by bestowing benefits from the State. This is in contrast to the the State using it's power of punishment to stop non-victimizing behavior. So, while I might not support the State banning non-abortive birth control (under penalty of law...use of power/coercion), I would actively oppose the State subsidizing non-abortive birth control (e.g., by handing out money...use of persuasion). Does that make sense?