VIDEO: What we know about deadly stabbing at Oakland's MacArthur BART station
"We have not received all the information in the case," Public Defender Brandon Woods explained. "We are missing police reports and basic information."
Cowell is accused of stabbing 18-year-old Wilson on the MacArthur BART platform in July. Her sister was also stabbed, but survived. Police have called the attacks random.
VIDEO: 'He was wiping off his knife' Sister of Nia Wilson recalls horrific attack
The Wilson family did not want to comment Friday morning after the hearing.
Cowell's attorney says he is struggling in jail.
"Anytime you are in custody it is difficult," said Woods. "But when you are suffering from mental illness it is difficult, it is hard."
The prosecution said it could not comment because of a gag order in the case. The next hearing is set for Oct. 26.
CONTINUING COVERAGE ON DEADLY BART STABBING:
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