Ricky Jackson was a Cleveland teenager in 1975 when he was sent to death row for a murder he didn't commit. He came within two months of his execution date when his sentence was reduced to life in prison because of a paperwork error. He was exonerated and walked free in 2014 after serving 39 years in prison -- the longest sentence by an exoneree in U.S. history. He is a sought-after speaker and recently gave a TED Talk at the Metropolitan Museum of Art in NYC.

(CNN) At the CNN Town Hall meeting between Hillary Clinton and Bernie Sanders last night, I had the privilege of asking Clinton how she could still support the death penalty in light of all the innocent people in this county in recent years who have been wrongfully convicted and sent to death row.

I said last night that I was "satisfied" with Clinton's answer, but that does not mean I agree with her. While I respect her opinion and her honesty, I completely disagree with her position on the death penalty.

The fact that we too often send innocent people to death row in this country can no longer be debated.

I ought to know. I was one of them.

In 1975, I -- along with my two childhood friends and co-defendants Wiley Bridgeman and Kwame Ajamu -- was wrongfully convicted and sent to death row for the murder of a white businessman that occurred in our predominantly poor and black neighborhood in Cleveland. We spent more than two years on death row before having our sentences reduced to life in prison.

I came within two months of my execution date but was saved by a lucky technicality -- the court made a mistake filling out the death penalty sentencing paperwork. Bridgeman and Ajamu later escaped death only because the U.S. Supreme Court struck down Ohio's death penalty statute as unconstitutional.

They both came even closer to death -- one of them came within a week of his execution date.

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If not for pure luck and chance, none of us would have been alive to see our exoneration nearly 40 years later.

Because of an investigation by the Cleveland Scene newspaper and the Ohio Innocence Project at the University of Cincinnati College of Law , we were vindicated and gained our freedom in November 2014. By that time, I had served 39 years in prison for a murder I didn't commit -- the longest sentence by an innocent person in U.S. history.

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I know that the death penalty does not deter. That can no longer be seriously debated

I also know that it is very expensive at a time when states are struggling financially and many are on the brink of bankruptcy. As an expensive government program with no proven track record of effectiveness, it is, indeed, the proverbial "bridge to nowhere." But I also know that it sends innocent people to death row, and sometimes kills them.

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Other innocent inmates -- in fact more than 150 of them -- have been lucky enough to have been exonerated and freed before their execution.

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Furthermore, I learned from my time on death row that even the guilty are worthy of salvation.

As an innocent and scared 18-year-old boy sent to death row, it was only the kindness and humanity of death row's guilty, who took me under their collective wing, that kept my sanity and maintained my faith in humanity. These inmates made horrible mistakes, and deserved to be punished, but they are not the animals our criminal justice makes them out to be.

A society should not be judged on how it treats its best, but rather on how it treats is lowest. And even the lowest are capable of incredible acts of humanity and are worthy of decency. They are worthy of God's grace, just as they bestowed grace upon me.

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When I asked Clinton why she still supports the death penalty, she said she supported it only for the worst of the worst: those who committed acts of mass killing or terrorism. I cannot accept that.

In cases such as those, the societal pressure to convict is at its highest. And when an intense pressure to convict is present, that is when the risk of convicting an innocent is greatest.

The death penalty is also not a deterrent in terrorism cases. In fact, death can serve the purpose of many terrorists who wish to become "martyrs" for their cause.

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During all the decades I sat in prison as an innocent man, I saw societal views gradually change. Not too many years ago, a Democratic candidate could not publicly support same-sex marriage and stand a chance of getting elected in a general election.

Now, a Democratic candidate could not be taken seriously if he or she didn't support same-sex marriage.

Likewise, no serious Democratic candidate should be able to support the death penalty. We have evolved. We have seen the evidence that the death penalty doesn't work and that it kills the innocent.

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Given this evidence, it is time that no candidate -- Democrat or Republican -- should be taken seriously if he or she supports capital punishment.

The fact that Clinton continues to hang on to this antiquated relic confuses me. She touts "criminal justice reform" -- and much reform is needed -- but she misses one of the lowest hanging pieces of fruit.

I said last night that I am an "undecided" voter. I hope that Clinton reconsiders her position on capital punishment before I do what I have been waiting my entire life to do: cast my first presidential vote as a free and vindicated man.