A mother who killed her brain-damaged son with heroin has been sentenced to a minimum of nine years behind bars for his murder.

Frances Inglis said she had "no choice" but to kill her 22-year-old son Tom in an "act of mercy" after he suffered severe head injuries when he fell out of a moving ambulance.

The 57-year-old tearfully told the jury she had done it "with love in her heart" to end his suffering.

But the judge told jurors to forget emotion and said no one has the "unfettered right" to take the law into their own hands.

Inglis, of Dagenham, east London, was found guilty of both murder and attempted murder.

She first tried to kill Tom in Sept. 2007 but it was not until Nov. 2008, while on bail for the first attempt, that she ended his life.

During the trial, Inglis wept as she described her despair at the "horror, pain and tragedy" of her son's helpless condition.

"For Tom to live that living hell - I couldn't leave my child like that," she told the Old Bailey.

She admitted ending her son's life but said, "I did it with love in my heart, for Tom, so I don't see it as murder."

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