Abortion,euthanasia, domestic abuse, gang related violence, terrorism, murder, mass shootings, expressions of hatred or racism and other acts contrary to the dignity of persons… all of these crimes cry out for justice. Yet we are a people of hope, and St. Paul reminds us that "in hope we were saved" (Rom 8:24).

Damon Thibodeaux spent 15 years in solitary confinement on Louisiana’s death row for a murder he didn’t commit. He was allowed out of his cell for only one hour each day to sit in the hallway or walk in a yard the size of a dog pen. In 2012 he became the 300th prisoner to be exonerated and freed through DNA testing, thanks to the work of the Innocence Project.

We are confident that we serve a God of life, of hope and mercy. We know that all human life is a gift from God, a gift that God charges us to protect. To be worthy of being called his disciples, Jesus urges us to love others as he has loved us (Jn 13:34-35). Our response then to a culture in which hostility towards others is commonplace, in which killing is often considered a legitimate solution to social problems, is to both live and proclaim a gospel of life, hope and mercy.

For people committed to upholding the sanctity of human life, the death penalty can present a challenge. Properly understood, however, Catholic teaching against the death penalty is both persuasive and eminently pro-life. It begins with the affirmation that human dignity applies to every human being, to victims as well as those who have committed crimes against life. Our teaching also holds that recourse to the death penalty may be justified only under the most narrow circumstance, namely, if it "is the only possible way of effectively defending human lives against the unjust aggressor" (Catechism of the Catholic Church [CCC], no. 2267). The teaching reminds us that if non-lethal means are capable of protecting society, these are preferable as "more in keeping with the concrete conditions of the common good and more in conformity with the dignity of the human person" (CCC, no. 2267).

Blessed John Paul II was instrumental in challenging the world to reconsider the use of the death penalty. In his 1995 encyclical Evangelium Vitae (The Gospel of Life, "EV"), he explained that, "The Gospel of God's love for man, the Gospel of the dignity of the person and the Gospel of life are a single and indivisible Gospel" (no. 2). Quoting the Second Vatican Council's Gaudium et Spes (no. 22), "By his incarnation the Son of God has united himself in some fashion with every man," he added that, "This saving event reveals to humanity not only the boundless love of God… but also the incomparable value of every human person" (EV, no. 2).

In the first chapter of EV, "The Voice of Your Brother's Blood Cries to Me from the Ground" (Gen 4:10), Blessed John Paul II presents the story of Cain and Abel to illustrate that God's mercy embraces even a murderer. Despite Cain's deliberate killing of his brother, despite his lack of remorse, his arrogance, his lies to God and utter callousness about what he had done ("I do not know [where Abel is]. Am I my brother's keeper?" Gen 4:9), God nevertheless refuses to take Cain's life as punishment. But he does not leave the crime unpunished. He tells Cain that he will not be able to grow crops and that he will be a fugitive and wanderer on the earth. Cain complains that such leniency is still too harsh, fearing that someone might kill him on sight.

God then reveals still greater mercy towards Cain, putting a mark on him "so that no one would kill him at sight" (Gen 4:15) and promising that "If anyone kills [you], [you] shall be avenged seven times" (Gen 4:15). Although Cain is spared execution, justice requires that he live the rest of his earthly life alone and outcast, but with time to reflect on his crime, to perhaps feel remorse and at last seek forgiveness and reconciliation with God.

The story of Cain and Abel shows that, though we reject and betray God through our sinfulness, his love for human beings is always faithful, merciful, compassionate and patient. Writing about this passage, Blessed John Paul II observed, "Not even a murderer loses his personal dignity, and God himself pledges to guarantee this" (EV, 9). We must never lose our conviction that even the worst offenders are our brothers and sisters in Christ.

From a purely secular perspective, it is a fact that simply because states have always exercised the power to kill persons convicted of murder or treason, it does not follow that this power always has been exercised wisely or well. Given mankind's seemingly infinite capacity to err, we must admit that the death penalty poses significant problems. With scandalous frequency, people on death row have later been shown to be innocent of the crime for which they were convicted. As of 2012, 141 people incarcerated on death row in 26 states have been exonerated and freed when conclusive evidence of their innocence was later discovered. But we cannot always rely on DNA evidence to demonstrate guilt or innocence because DNA evidence exists in only 10 percent of cases.

Even if the death penalty were always imposed without error, should we support its use? We teach that killing is wrong by responding with mercy and justice, not more killing. We don't want a government that kills when society can be protected fully by the bloodless means of life imprisonment. By fostering a spirit of vengeance, which should have no role in the administration of justice, the death penalty contributes to the increasing disrespect for human life in our culture.

Today a growing movement in the United States, led by Catholics, opposes the use of the death penalty. As a result, more states are restricting or abolishing its use, but many other states retain this penalty.

As Catholics, we believe and put our hope in a merciful and loving God. We are conscious of our own brokenness and need for redemption. Our Lord calls us to imitate him more perfectly by witnessing to the inherent dignity of every human being, including those whose actions have been despicable. Our faith and hope is in the mercy of God who says to us, "Blessed are the merciful for they shall be shown mercy (Mt 5:7) and "I desire mercy, not sacrifices" (Mt 9:13). As Christians we are called to oppose the culture of death by witnessing to something greater and more perfect: a gospel of life, hope and mercy.

Charles J. Chaput, Archbishop of Philadelphia, recently summed up the case against the death penalty in these words: "As children of God, we're better than this, and we need to start acting like it. We need to end the death penalty now." Let us then join in efforts to end the death penalty and show that we are people of life, hope and mercy.

Anthony Granado is a Policy Advisor in the Office of Domestic Social Development of the United States Conference of Catholic Bishops.