Definition - What does Premeditation mean?
Premeditation is the act of committing a crime with forethought and planning. It is a deciding factor in whether or not a person is charged with a more serious crime than a crime of the moment. Premeditation can be proven through any act that shows the person who committed the crime could not have done so without having brought in elements through advance planning.
Justipedia explains Premeditation
The reason premeditation is considered more severe than a regular crime. Premeditation is singled out because the basis of law is the application of consideration and intent. In general, a person who does not intend to commit an act is given a degree of leniency for that reason. A person that planned an act, especially a heinous one, is more of a danger to society and receives a longer sentence. In some states, premeditated murder convictions are the death penalty.