The defense is asking investigators to explain how they separated fantasy from realty in the graphic cannibalism plot a New York City cop is on trial for.

One of the FBI agents testifying in the trial on Wednesday was pressed to explain how they can determine where fantasy ends and reality begins after reading aloud several dozen Internet chats in which participants boasted of plans to cook and eat human flesh.

The FBI claims its analysis of 40 of Gilberto Valle's emails and chats were evidence he wanted to abduct, torture and eat women.

But as one agent also testified trial that there were thousands of others the FBI concluded were mere fantasy, Attorney Robert Baum’s cross examination aimed to show little or no distinction existed between chats or emails the FBI deemed real evidence of a crime and those dismissed as fantasy.

Baum attacked FBI agent Corey Walsh's statement that 40 of the thousands of Internet communications of Officer Gilberto Valle that he reviewed contained "elements of real crimes." Valle is accused in Manhattan federal court of conspiring to kidnap, kill and eat women he knew, including his wife.

Walsh conceded that some chats or emails considered fantasies contained photographs and names of real women and dates and references to past crimes, the kind of factual information that prosecutors have insisted proves Valle meant to carry out gruesome crimes including kidnapping, rape, torture, murder and cannibalism.

The agent also conceded that no women were kidnapped or harmed and that Valle never had contact with his supposed co-conspirators outside the Internet.

In addition, the agent said, no evidence of a crime was found in Valle's apartment besides a computer.

For two days, Walsh has testified about chats Valle participated in last year with a New Jersey co-defendant and two supposed co-conspirators, a man in Great Britain and Khan, both of whom posed on the Internet as veterans of cannibalism who could teach Valle cannibalism skills.

The 28-year-old Valle has pleaded not guilty to charges for conspiring to kidnap a woman and using a law enforcement database to amass personal information on potential targets.

Based on reporting by the Associated Press.

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