Innocent people get executed in the US all the time, especially in the gung-ho state of Texas. It's one of the most potent arguments against the death penalty, and all the facts are in the arguments favor. It's time to get rid of the death penalty once and for all.
Yes, I do believe that innocent people have been executed in the United States. I believe this happened more frequently before we had knowledge of DNA testing, but I also think innocent people have been killed when we did have it. Sometimes evidence doesn't come out for years, and sadly, someone innocent has had to pay the price.