A man charged over the mysterious disappearance of a Queensland gem miner allegedly made confessions to a police informant while in custody, a court has heard.
David Hanson was last seen alive by his daughter when the pair met for breakfast in February 2014 on the day he was due to fly to the East African country of Tanzania.
But the 71-year-old never arrived at the airport and hasn't been seen since.
Judd Mitchell Lees was charged in December 2015 with being an accessory after the fact to Mr Hanson's murder and interfering with his corpse.
The Brisbane Magistrates Court heard on Thursday the case against Lees hinged on alleged confessions he made while in custody to a police informant, who was wearing a recording device.
Lees' lawyer, James Wallace, said without the informant's evidence there was no case for a jury to hear.
"He's the primary and really only witness able to give any sort of direct evidence about my client's alleged involvement in this matter," Mr Wallace said.
"This case hinges so clearly on his (the informant's) word."
Mr Hanson's body has never been found but detectives said in November 2014 they believed he was killed at a car-detailing business on Timms Court in Woodridge, south of Brisbane.
No one has been charged with his murder or manslaughter.
Lees is due to face a committal hearing in the same court on May 26.