A Toronto jury is hearing that a woman on trial for murder was the “mastermind” behind the abuse of her stepdaughter, whose body was found in a burning suitcase.

In her opening remarks, Crown prosecutor Mary Humphrey said Elaine Biddersingh turned her stepdaughter Melonie’s life into a nightmare when the girl was in her care.

Biddersingh has pleaded not guilty to first-degree murder in the death of the 17-year-old girl, whose body was found in a charred suitcase in an industrial parking lot in 1994 but identified only in 2012, through DNA testing.

Melonie came to Canada from Jamaica in 1991 with two brothers to live with her father and her stepmother. Humphrey said the children came to Toronto seeking a better life but were instead treated like slaves.

“Melonie was beaten, she was starved, she was confined in the apartment,” said Humphrey.

“She was drowned or nearly drowned inhaling water shortly before her death. She was stuffed into a suitcase, driven to an isolated area, doused in gasoline and set on fire.”

A key witness, Humphrey suggested, would be Melonie’s older brother, Cleon, who is expected to testify about the way in which Melonie’s abuse worsened over time.

“Cleon will describe how Elaine was the mastermind behind the abuse and (Melonie’s father) Everton was the enforcer,” she said.

Melonie’s father was found guilty in January of first-degree murder in his daughter’s death.

The jury at the current trial was told to disregard that conviction as “completely irrelevant” to the case before them.