Luigi Mangione's lawyers have urged a federal judge in New York to block prosecutors from seeking the death penalty for their client, who is charged with killing UnitedHealthcare CEO Brian Thompson.

In a court filing, Mangione's lawyers argued that US Justice Department officials should be precluded from seeking the death penalty because of actions that had violated his due process rights.

They said these included "staging a dehumanising, unconstitutional 'perp walk' where he was televised, videotaped and photographed clambering out of a helicopter in shackles on his way to his initial appearance".

"Because of the blatant, intentional and damaging nature of this torrent of prejudice from multiple public officials, mainly the United States Attorney General, from the inception of this cas

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