OXFORD, Miss. (AP) -- Investigators haven't found any ricin in the house of a Mississippi man accused of mailing poisoned letters to President Barack Obama, a U.S. senator and a local judge, according to testimony Monday from an FBI agent.
Agent Brandon Grant said that a search of Paul Kevin Curtis' vehicle and house in Corinth, Miss., on Friday did not turn up ricin, ingredients for the poison, or devices used to make it. A search of Curtis' computers has found no evidence so far that he researched making ricin.
Defense lawyers for Curtis say investigators' failure to find any ricin means the government should release their client. That lack of physical evidence could loom large as a detention and preliminary hearing continues Tuesday morning. U.S. Magistrate Judge J. Allan Alexander ended the hearing after lunch Monday, citing a personal schedule conflict.
Through his lawyer, Curtis has denied involvement in letters sent to Obama, Mississippi Republican Sen. Roger Wicker, and a Lee County, Miss., judge. The first of the letters was found April 15.
"There was no apparent ricin, castor beans or any material there that could be used for the manufacturing, like a blender or something," Grant testified. He speculated that Curtis could have thrown away the processor. Grant said computer technicians are now doing a "deep dive" on the suspect's computers after initially finding no "dirty words" indicating Curtis had searched for information on ricin.
Christi McCoy, who is leading the defense for Curtis, said the government doesn't have probable cause to hold her client and his history of problems related to bipolar disorder are not enough to keep him in jail.
"The searches are concluded, not one single shred of evidence was found to indicate Kevin could have done this," McCoy told reporters after the hearing.
She questioned why Curtis would have signed the letters "I am KC and I approve this message," a phrase he had used on his Facebook page, and then thrown away a processor used to grind castor beans. And she said that in any event, Curtis is not enough of an imminent danger or flight risk to justify holding him without bail.
"If they continue to demand his incarceration, it's basically bad faith," McCoy said. "Now, surely they are satisfied that there is no immediate threat from Kevin Curtis, and we want him released."
McCoy said in court that someone may have framed Curtis, suggesting that a former business associate of Curtis' brother, a man with whom Curtis had an extended exchange of angry emails, may have set him up.
Still, Grant testified that authorities believe that they have the right suspect.
"Given the right mindset and the Internet and the acquisition of material, other people could be involved. However, given information right now, we believe we have the right individual," he said.
Grant said lab analysis shows the poison is a crude form that could have been created by grinding castor beans in a food processor or coffee grinder.
"That would be a low-tech way of doing it. You're just blending up the beans to get the ricin that's on the inside on the outside," Grant testified.
The detention and preliminary hearing began Friday in U.S. District Court in Oxford, Miss. More witnesses besides Grant are expected Tuesday.
Federal investigators believe the letters were mailed by Curtis, an Elvis impersonator who family members say suffers from bipolar disorder. He wore an orange jumpsuit from the Lafayette County Detention Center in court Monday, and was quiet and attentive, sometimes whispering to McCoy.
Grant testified Monday that processing codes printed on the letter indicated they had been mailed from Tupelo, and that investigators were still trying to figure out from the codes exactly where they had been mailed from.
Grant testified Friday that authorities tried to track down the sender of the letters by using a list of Wicker's constituents with the initials KC, the same initials in the letters. Grant said the list was whittled from thousands to about 100 when investigators isolated the ones who lived in an area that would have a Memphis, Tenn., postmark, which includes many places in north Mississippi. He said Wicker's staff recognized Curtis as someone who had written the senator before.
Grant also testified that there were indentations on the letters from where someone had written on another envelope that had been on top of them in a stack.
The indentations were analyzed under a light source and turned out to be for Curtis' former addresses in Booneville and Tupelo, though the street name in one of the addresses was spelled wrong, Grant said.