Perverting the course of justice carries a maximum sentence of life imprisonment, although the average sentence is around 10 months.
Both 58-year-old Chris Huhne and economist Vicky Pryce, 60, have been warned to be under no illusion about what punishment they face.
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A deal is believed to have been reached with official confirmation likely on Friday.
The woman is described as being around 50 years old with short spikey purple hair.
No one gave him a chance - but Donald Trump has just pulled off one of the greatest feats in modern American political history.