From the catechism. I think think this is a good summary of Catholic teaching and is consistent with the universal pro-life stance of the Church. My only point of argument is with the last paragraph. The arguable point is what actually constitutes adequate public safety? I think each of us has his own answer to that, but I personally don't consider that society is 'safe' just because a monster is behind bars. There are truly evil people out there that remain threatening to the whole of society. Maybe its all the training I've had that preaches 'eliminate the threat.'
Oh, and my cut and paste erased the paragraph numbers. Sorry about that.
Legitimate defense
The
legitimate defense of persons and societies is not an exception to the
prohibition against the murder of the innocent that constitutes
intentional killing. "The act of self-defense can have a double effect:
the preservation of one's own life; and the killing of the aggressor.
. . . The one is intended, the other is not."65
Love toward oneself remains a fundamental principle of morality.
Therefore it is legitimate to insist on respect for one's own right to
life. Someone who defends his life is not guilty of murder even if he is
forced to deal his aggressor a lethal blow:
If a man in self-defense uses more than
necessary violence, it will be unlawful: whereas if he repels force with
moderation, his defense will be lawful. . . . Nor is it necessary for
salvation that a man omit the act of moderate self-defense to avoid
killing the other man, since one is bound to take more care of one's own
life than of another's.
66 </dd>
</dl>
Legitimate defense can be not only a right but a grave duty for one who
is responsible for the lives of others. The defense of the common good
requires that an unjust aggressor be rendered unable to cause harm. For
this reason, those who legitimately hold authority also have the right
to use arms to repel aggressors against the civil community entrusted to
their responsibility.
The efforts of the state to curb the spread of behavior harmful to
people's rights and to the basic rules of civil society correspond to
the requirement of safeguarding the common good. Legitimate public
authority has the right and duty to inflict punishment proportionate to
the gravity of the offense. Punishment has the primary aim of redressing
the disorder introduced by the offense. When it is willingly accepted
by the guilty party, it assumes the value of expiation. Punishment then,
in addition to defending public order and protecting people's safety,
has a medicinal purpose: as far as possible, it must contribute to the
correction of the guilty party.67
Assuming that the guilty party's identity and responsibility have been
fully determined, the traditional teaching of the Church does not
exclude recourse to the death penalty, if this is the only possible way
of effectively defending human lives against the unjust aggressor.
If, however, non-lethal means are sufficient to defend and protect
people's safety from the aggressor, authority will limit itself to such
means, as these are more in keeping with the concrete conditions of the
common good and more in conformity to the dignity of the human person.
Today, in fact, as a consequence of the possibilities which the state
has for effectively preventing crime, by rendering one who has committed
an offense incapable of doing harm - without definitely taking away
from him the possibility of redeeming himself - the cases in which the
execution of the offender is an absolute necessity "are very rare, if
not practically nonexistent.