By Teresa Carson
PORTLAND (Reuters) - Prosecutors must give defense lawyers a tape recorder at the center of the case against a Somali-born teen charged with plotting to blow up a Christmas-tree lighting event in Portland, a judge ruled on Wednesday.
The decision came during a pre-trial hearing for 19-year-old Mohamed Osman Mohamud, who was charged in November with attempting to use a weapon of mass destruction at the annual tree lighting ceremony in downtown Portland.
Prosecutors say the Mohamud tried to detonate what he believed was a van packed with explosives at the crowded event -- actually a fake bomb provided to him by undercover agents posing as terrorists.
Mohamud, who attended the hearing, shackled at the ankles and wearing a blue jail uniform, is scheduled for trial beginning on April 10, 2012.
Defense attorneys sought to examine the tape recorder after prosecutors said that it failed during a key July 30 conversation between Mohamud and undercover operatives who he allegedly believed to be co-conspirators.
"The government has to be as forthcoming as possible" in providing materials gathered during the investigation, U.S. District Judge Garr King said during the hearing, which was dedicated in large part to discovery matters.
But King also urged defense attorneys to "be as specific as possible" in their requests.
Mohamud's lawyers, who are expected to mount an entrapment defense, have asked for a broad array of materials from the undercover sting operation.
Assistant U.S. Attorney Ethan Knight told the judge that the government had provided 95 to 98 percent of the materials in its possession, including more than 70 computer disks, more than 6,000 pages of written materials, hundreds of hours of video and three hard drives from Mohamud's computers.
King told Mohamud's lawyers they could not have polygraph materials from an unrelated criminal investigation of Mohamud or information on the training of the law enforcement agents involved in the investigation.
(Editing by Dan Whitcomb)