The Coroner's Court hearings into the death began today in a meeting room at Forsyth Barr Stadium in Dunedin.
The hearing is expected to last up to two weeks, and nine counsel were in the court yesterday to act for witnesses.
Mr Davis (30) died after entering the facility as a remand prisoner, after entering with drugs concealed in his body.
His mother, Victoria Davis, has said staff failed in their duty of care, and let her son die in at-risk cell with no medical help.
Before Otago-Southland coroner David Crerar, a corrections officer told the court he had monitored telephone calls as part of his role at the facility.
On February 8 and February 9, he monitored a call between Mr Davis and a man connected to the Mongrel Mob gang.
The calls indicated Mr Davis planned to bring drugs into the prison.
There was discussion between the men of ''candy'', which the corrections officer said he understood to be slang for prescription medication.
The hearing is continuing.
