AN INQUEST into the death of the man gardaí believe shot dead Dublin woman Donna Cleary and who later died in garda custody will hear that he was given a Rohypnol tablet in the hours before he died from methadone poisoning.

Gardaí believe Dwayne Foster (24) indiscriminately opened fire at a house party in Coolock in March 2006, killing Cleary, a 22-year-old mother of one.

For the first time at an inquest, garda videotapes of a suspect's interviews with detectives are to be shown to determine whether his health was deteriorating during questioning. The inquest begins tomorrow and is listed for hearing all week.

Foster was taken to Coolock garda station shortly after midnight of the morning of 6 March 2008, less than 24 hours after Cleary was shot at the house party. He saw a GP shortly after his arrival who gave him two paracetamol tablets.

He then saw another GP at around 10am the next day who prescribed him 30ml of methadone because Foster requested it saying he was a regular user of the drug, the inquest will hear.

At about 8pm the same day, after Foster had been interviewed by detectives, the GP was again contacted and prescribed Foster another 30ml of methadone and asked that gardaí take him to the ear, nose and throat specialist at Beaumont hospital as he was bleeding from his ear.

Gardaí took the suspect to the hospital where he was examined within minutes before being taken back to the station for more questioning. The specialist at Beaumont concluded the suspect has soft tissue injury to his ear that was causing bleeding.

The GP who twice prescribed methadone for Foster also left a Rohypnol tablet with gardaí to be given to the suspect should he need it later in the night to help him sleep.

He was questioned by gardaí until shortly before midnight before being returned to his cell and was given the Rohypnol tablet as he requested something to help him sleep. Rohypnol is the sedative which has achieved notoriety as a "date rape" drug. At about 2.30am that morning, Foster was found unresponsive in his cell and was rushed to hospital where he was pronounced dead.

While Foster told the GP he was a methadone user, the inquest will probe whether he was only an occasional user of the drug, explaining how he died in his sleep from methadone poisoning as 60ml would be a high dosage of methadone for unaccustomed users.

It will also be raised whether the sedative Rohypnol played a part in his death. Some suspects in custody request methadone under false pretences as it helps them "zone out" during garda interviews, according to a garda source. Foster had recently recovered from aggressive throat cancer.

Up to 40 people are listed as witnesses to give evidence at the inquest into the death in custody. As well as several gardaí, the two GPs who treated Foster while he was in custody will be called to give evidence as will the specialist from Beaumont.

Two of the men who were arrested with Foster in Co Kil­dare on suspicion of involvement in the shooting of the young mother are also scheduled to give evidence.

One of these men is serving a prison sentence for another crime and will be taken to Dublin City Corner's Court from his prison cell. It will be alleged that during the course of his arrest, Foster may have been ill-treated by gardaí leading to bleeding from his ear the next day.