EDIT: I meant to say how many people serving life sentences. But I suppose it applies to people on death row who never actually get put to death.
You realise you could use the same statement to defend the death penalty? There are dozens of people in the UK who have been killed by people on life sentences that have been released but in earlier times would have face the death penalty.
I'm not pro-death penalty. I don't trust governments enough. I'd be happy with whole of natural life (i.e. no release ever) sentences.
Actually not that many do: http://abcnews.go.com/US/story?id=90978&page=1
Those people who are "OK with a few false positives" include legislators, the president, governors, district attorneys, prosecutors, police, etc. In some cases, DAs and other law enforcement officials have fought tooth and nail to prevent old cases from being reopened, since they feared being embarrassed by the truth more than they feared an innocent person being in prison or getting executed. (I think that if anyone deserves the death penalty, it's those who knowingly send innocent people to be executed to further their own careers. That should be considered murder.)
Why shouldn't every case that was based on hair evidence (not just the 2000 that had technical legal errors) deserve to get a DNA test? If they still have the hair sample, they can test the hair's DNA against that of the prisoner. I'd suspect the reason they don't do this is that the government fears that exposing how fallible the legal system is will lead to massive public unrest.
And then there's the whole corrupt plea-bargaining system that induces people to plead guilty to crimes they didn't commit because they're afraid of being hit with the death penalty if they go to trial and lose (which is a high probability for poor people represented by public defenders).
All of these things are possible because of laws which our elected representatives have enacted and enforce.
[1] http://www.deathpenaltyinfo.org/federal-laws-providing-death...
There are (at least) 51 governments in the USA. For the nth time, it's not a monolithic entity. After all, we have a good numbers of states that have banned or imposed moratoria on the death penalty too, and those states obviously have no compelling interest in preventing scrutiny of its reliability.
massive public unrest
No chance. People (collectively speaking) are indifferent to perfectly well-documented failures of the legal system as it is.
Chance would be fine thing.
Compared to other states, California executes very few criminals. Over the last 10 years, only three inmates have been killed. Compared to Texas which, over the same time frame, has executed 263 inmates [2].
However, California currently has the most inmates on death row (727) of any state. Since California doesn't execute the inmates it puts on death row, they end up costing the tax payers. An inmate on death row costs the state almost four times as much as a regular inmate ($175k versus $47k)[3].
[1]: http://en.wikipedia.org/wiki/California_Proposition_34_%2820...
[2]: http://en.wikipedia.org/wiki/Lists_of_people_executed_in_Tex...
[3]: http://www.motherjones.com/mojo/2013/02/death-penalty-califo...