Is baptizing someone without consent valid? (Roman Catholic view)

Question

Stemming from this question Is it valid to baptize multiple persons at once?, the question gives the scenario of one person baptising multiple people on a plane that is going to crash. The bit that confused me was towards the end when it says:

and that air pressure has been lost leaving [the one doing the baptising] as the only one conscious

There is a comment as well:

consent doesn't matter to the validity of baptism

According to the Roman Catholic church, if you baptise an adult who is not a believer and has not asked to be baptised (has not given consent), is that a valid baptism?

Answer 1

I think you'll find the section on Baptism in the Code of Canon Law helpful in answering your question.

Code of Canon Law: Title 1 - Baptism

To summarize a bit (please check out the link for the lion's share of details):

• There is more than one way to be baptized, not all of which require a minister or other baptized person to be present. (e.g. the Baptism by Desire referenced by @Alypius above.) One form doesn't even require the recipient to be aware, but it's a special case (infants) that assumes the guardians have the infant's best interests at heart.
• Consent is mandatory, and the person must be alive. This is where Catholic baptism parts ways from Mormon baptism. In the latter, it is acceptable to baptize the dead.

So, if the people on the plane expressed a desire to be baptized, and gave their consent, it matters little that they're conscious or not when the sacrament is conferred. An infant isn't cognizant of the act, yet it is acceptable to baptize the infant (for many reasons that you'll find in "illuminated" versions of the Code of Canon Law.)

Here's another pretty decent source of info (goes into much greater detail than the Code of Canon Law): Catholic Encyclopedia

Answer 2

You asked:

According to the Roman Catholic church what happens to a non-believer when they die?

I believe Rome teaches that a person must have partaken of the sacraments, and believe in Christ.

If any one saith that the sacraments of the New Law are not necessary unto salvation...and that without them, or without the desire thereof, men obtain from God, through faith alone, the grace of justification...let him be anathema (The Canons and Decrees of the Council of Trent. Found in Philip Schaff, The Creeds of Christendom (Grand Rapids: Baker, 1919), Canon IV, p. 119).

In addition to this penance would also be necessary:

Penance is...necessary because we must expiate and make reparation for the punishment which is due our sins...We make satisfaction for our sins by every good act we perform in the state of grace but especially by prayer, penance and the practice of charity (John Hardon, The Question and Answer Catholic Catechism (Garden City: Image, 1981), Question #1320).

The mass is also necessary to cleanse from sins committed after baptism:

In this divine sacrifice...that same Christ is contained and immolated in an unbloody manner who once offered himself in a bloody manner on the altar of the cross...This sacrifice is truly propitiatory...If any one saith, that the sacrifice of the mass is only a sacrifice of praise and thanksgiving; or that it is a bare commemoration of the sacrifice consummated on the cross, but not a propitiatory sacrifice...and that it ought not to be offered for the living and dead for sins, pains, satisfactions and other necessities: let him be anathema (The Canons and Decrees of the Council of Trent. Found in Philip Schaff, The Creeds of Christendom (Grand Rapids: Baker, 1910), Doctrine on the Sacrifice of the Mass, Chp. II, p. 180, Canon III).

So, if an unbeliever did not do these things he would be hell bound according to Rome.

You also asked:

Is there any difference for a non-believer who has been baptised compared to a non-believer who hasn't been baptised?

One must first ask the question, 'Is Catholic baptism valid?'. I do not believe it is. But even assuming that it was, according to the Catholic position, the person would still be bound to hell, as he has not partaken of baptism and has no faith in Christ.

Now, for the sake of openness, I will state that I am not a Catholic, but a reformed protestant.