An inquiry is being held in a Calgary courtroom to determine how a psychiatric patient at the Rockyview Hospital drowned in a nearby reservoir.

Witnesses told a judge that Trinh My Tran, 52, suffered from schizophrenia and had not been taking her medication for weeks when she was admitted to Rockyview Hospital.

She died two months later, in June 2011, when her body was pulled from the nearby Glenmore Reservoir.

Her psychiatrist testified Tuesday that Tran did not show any sign of being suicidal. A doctor and nurse also testified she had continually improved in care and had earned passes to leave the hospital unescorted.

On the day she died, Tran had been given a pass to leave her unit, but had promised to stay on hospital property. She was found hours later in the Glenmore Reservoir.

It has not been determined whether her drowning was an accident or suicide.

The judge in the inquiry is not responsible for finding blame in the case, but is expected to make recommendations to help prevent a similar case in the future.