How long is someone in jail before they are executed?

Usually 18-20 years and more, they move very slowly and have many appeals.

When you ask a state to take the life of person it is a very serious request and before the execution occurs the state must be satisfied that the person has committed the crime. This means the courts will give "special consideration" when deciding to hear a case on appeal that regards a death sentence. It also means, unlike other cases where the court of appeal can decide not to hear the case but on a first appeal for a death sentence case they must hear it.

For someone on death row it means the date of execution is usually years off due to most appellate courts having a large case load. If it is appealed from, almost all are, the court of appeals it then goes to the Supreme Court of that state then to the US Supreme Court. From there other issues can be raised including Writ of Habeus Corpus which asks the court to review the reason why the person is being detained and it is a last attempt to keep the person from being executed in the courts.

Once the options in the courts have been exhausted then the person's attorney can apply to the governor for the sentence to be committed to life in prison or pardoned. Most of the time the governor will say no. The time from conviction to actual execution varies. Why? Such factors include the state's court system structure, how many cases need to be reviewed, what can be appealed, if a Writ of Habeus Corpus is filed, and if the governor is asked to intervene. So to answer your question regarding the length of time from conviction to execution there is no set time due to the fact there are many factors that influence the length of time.