'American Sniper' trial: Chris Kyle killer 'used Seinfeld to fake insanity', says prosecution witness

Chris Kyle killer 'used Seinfeld to fake insanity'

American sniper Chris Kyle had over a 100 'kills' to his name (AP)

The man accused of killing “American Sniper” author Chris Kyle may have learned how to fake insanity from watching the TV programme “Seinfeld”, it has been claimed.

A prosecution witness told the court at the trial of Eddie Ray Routh that there were “suspicious” similarities between the apparently unsettled ramblings of the defendant and certain storylines on the hit US sitcom.

Routh, 27, is accused of fatally shooting Kyle his friend Chad Littlefield multiple times at a Texas gun range in February 2013. Routh fled the scene in Kyle’s pickup truck and has since admitted the killing, but his lawyers say he is innocent of murder on the grounds of insanity.

Testifying for the prosecution, forensic psychologist Dr Randall Price said he believed Routh to be suffering from “cannabis-induced psychosis”, a paranoid disorder worsened by the use of alcohol and marijuana.

He and another prosecution expert, Dr Michael Arambula, said Routh's actions do not meet the legal definition of insanity under state criminal law because, as Arambula put it to the court: “Any time intoxication is present, it’s game over.”

Price repeatedly accused Routh of “setting the stage” for an insanity defence with stories about “seeing neighbours and friends as turning into pig-human hybrids”.

He suggested Routh may have gotten the idea from “Seinfeld” or another TV show called “Boss Hog”. In one “Seinfeld” episode cited in court, the character Kramer says he believes he has discovered a “pig-man” roaming the halls of a hospital.

“I don't know for a fact that he saw that episode of ‘Seinfeld’, but I do know that he's watched ‘Boss Hog’, said Price. “For a long time, he's talked a lot about pigs to a lot of people. So it's suspicious.”

Bradley Cooper plays sniper Chris Kyle in blockbuster American Sniper (AP)

A defense witness, Dr Mitchell H Dunn, testified earlier that Routh had schizophrenia and showed signs of the illness for as long as two years before the February 2013 shootings, and in such a way that could not be faked.

The trial was suspended due to an ice storm in the area on Monday, but rebuttal witnesses were expected to take the stand on Tuesday after which the jury were to hear each side’s closing arguments.

Proceedings have met with intense public interest following the success of the film “American Sniper”, based on Kyle’s story as the sniper with the most confirmed kills in US military history.