The great-grandson of E I du Pont, who in 1802 founded the chemicals giant that created such universal substances as nylon and Teflon, John du Pont, 58, is believed to be the richest man ever to be tried in America for murder.
About the crime itself little dispute is expected. Defence lawyers have indicated that they accept that on 26 January last year, their client went to the house of David Schultz, who was the coach at a wrestling centre owned by Mr du Pont on the estate, and killed him with three bullets in the chest. Wrestling was a passion of Mr du Pont; Mr Schultz was hoping to compete in the 1996 Olympic Games.
The shooting was followed by a dramatic 48-hour police siege at the 'Foxcatcher' estate, outside Philadelphia. Mr du Pont, who had holed himself up inside his mansion, was finally detained after he emerged to check a heating boiler.
At issue, however, will be the mental state of Mr du Pont. In court filings, the defence team stated: "At the time of the commission of the act, the defendant was labouring under such a defect of reason, from disease of the mind... as to not know that what he was doing was wrong." The defence strategy is to have at least the first-degree murder charge dismissed on grounds of insanity.
After his arrest last year, Mr du Pont was admitted to a state mental institution and treated for severe schizophrenia. His trial had been delayed until this month by Judge Patricia Jenkins because he was considered unfit to assist in his own defence.
His once clean-shaven face now framed by a straggling white beard, Mr du Pont is said to be suffering from extravagant delusions that he is either Jesus Christ, the Dalai Lama or the last child of the Russian royal family. He has also claimed that he is the victim of an international assassination plot.
He has also told doctors that he believes that clones have been made of him by his enemies. Indeed, it was not John du Pont that killed Mr Schultz, he said, it was one of his clones.