James Holmes may pay the ultimate price for allegedly shooting into a crowded movie theater last summer in Aurora, Colorado, killing 12 people and wounding 58 others.
Prosecutors announced Monday that they will seek the death penalty against Holmes.
In court documents filed last week, Holmes' attorneys wrote that their client would be willing to plead guilty to more than 150 charges if he would be allowed to spend the rest of his days in prison with no parole, but prosecutors rejected that deal.
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Holmes’ attorneys have indicated they could seek a mental health defense if the case goes to trial. In an earlier proceeding, Holmes’ attorneys said their client is mentally ill, but they needed additional time to research an insanity plea before moving forward with it.
His attorneys could argue that their client has "diminished capacity," a term that the Colorado Bar Association relates to a person's ability or inability "to make adequately considered decisions" regarding his or her legal representation because of "mental impairment or for some other reason."
HLN’s legal experts say even if Holmes is convicted, it may take 10 years before he is put to death, because of the long appeal process.
Colorado reinstated the death penalty in 1976, and since then has only executed one convict. Three people are on death row in Colorado right now.