These are the feelings that Amnesty International USA has toward the death penalty:
They believe that the death penalty is the ultimate and irreversible denial of human rights. By working toward the abolition of the death penalty worldwide, Amnesty International USA's Program to Abolish the Death Penalty looked to discontinue the cycle of violence created by a system consumed with economic and racial bias and corrupted by human error. The death penalty is a violation of human rights. More than half the countries in the world have now abolished the death penalty in law or practice.
The USA is executing criminals who have been diagnosed with mental illness. In 1986, in Ford v Wainwright, the Supreme Court ruled that the execution of the insane violates the Constitution's ban on "cruel and unusual punishments." It is impossible to know how many of those executed suffered from mental problems, but estimates go as far as 10%. The execution of those with mental illness is clearly forbidden by law in literally every country in the world. Despite these standards, the USA continues to execute people with clinically-labeled mental illnesses.
Another reason Amnesty is against the death penalty is because, it can claims the lives of innocent people. Since 1973, more than 115 people have been released from death rows throughout the country due to evidence of their wrongful convictions. Just in 2003 alone, 10 innocent defendants were released from death row. Some factors that can lead to wrongful convictions are: inadequate legal representation, police and prosecutorial misconduct, perjured testimony and mistaken eyewitness testimony, racial prejudice, jailhouse snitch testimony, suppression and/or misinterpretation of mitigating evidence, and community/political pressure to solve a case. All these factors can lead to the killings of many innocent people in the USA.
There are numerous more reasons why...