A defendant sentenced to "life without the possibility of parole" don't get out.  Defendants sentenced to "life with the possibility of parole" sometimes do get parole, which is for the rest of their lives.  Even one instance of a released offender committing a new capital crime is obviously and understandably cause for outrage, and when it occurs the spike in support for capital punishment is predictable and understandable.  But the fact is that it does not happen very often; and it does not affect the teaching of the church.  The justice system is not perfect, either in finding in guilt or in predicting who will re-offend.  That's reason both to reject the death penalty and to be scrupulous about which defendants are granted parole.