What was the first U.S. state to end the death penalty except for treason?

In 1846, Michigan became the first state to abolish the death penalty for all crimes except treason. Later, Rhode Island and Wisconsin abolished the death penalty for all crimes. Michigan replaced the death penalty with life imprisonment. For all intents and purposes, Michigan was the first English speaking jurisdiction in the world to abolish capital punishment.

Currently, worldwide, the United States is the only Western country applying the death penalty; and, America was the first to develop lethal injection as method of execution, which has since been adopted by five other countries.

Now, specifically in the U.S., thirty two (32) states and the federal government still use capital punishment. In 2015, twenty eight (28) offenders were executed in America.