Undercover cops could face Morcombe trial

Undercover police officers, a zoologist and SES volunteers are among more than 150 potential witnesses who could be called to give evidence in the trial of Daniel Morcombe's accused killer.

The names of 158 potential witnesses and their occupations were read to members of the jury in the murder trial of Brett Peter Cowan on Monday.

The potential witnesses also include Daniel's parents Bruce and Denise Morcombe and his twin brother Bradley and older brother Dean.

Three people identified only as covert police officers from Western Australia are also on the witness list.

Several SES volunteers, a bus driver from Daniel's home suburb of Palmwoods, a zoologist and a professor of anatomy were also named as potential witnesses in the trial, which is expected to run for six weeks.

A jury of six men and six women was selected in the Brisbane Supreme Court after Cowan, 44, pleaded not guilty to murdering Daniel on December 7 2003 at the Glass House Mountains on the Sunshine Coast hinterland.

He also pleaded not guilty to indecent treatment of a child and interfering with a corpse.

Daniel's parents and brothers watched from the crowded public gallery when Cowan entered his pleas.

Justice Roslyn Atkinson is expected to open the trial on Monday afternoon.

Daniel was 13 when he disappeared while waiting for a bus at Woombye on the Sunshine Coast in 2003. He'd been on his way to buy Christmas presents for his family.

His remains were found in bushland at the Glass House Mountains in 2011.

Mr and Mrs Morcombe have relentlessly campaigned for justice for Daniel and have dedicated their lives to increasing awareness about child safety.

The foundation they have set up in their son's name works with schools across the country to educate children about how to keep themselves safe.