A more thorough explanation:

Definition: A lifer is a nonremovable inmate, meaning they cannot be deported even though they would ordinarily be deportable. This is because the United States does not have diplomatic ties with the inmate's country of origin. Another term for a lifer is an indefinite detainee.

• An undocumented immigrant from a country that the United States does not have diplomatic ties with is arrested and detained. They are unable to be deported and become a lifer.
• A person seeking asylum from a country that the United States does not have diplomatic ties with is detained and unable to be deported. They become a lifer.

These examples illustrate how a person can become a lifer if they are unable to be deported due to the lack of diplomatic ties between their country of origin and the United States. This can happen to both undocumented immigrants and those seeking asylum.