A Midland lawyer has won a landmark case in the High Court - upholding a man’s right to inherit under the will of his partner following a legal challenge by her daughters.

Robert Weston, head of the contentious probate team at mfg Solicitors, helped Michael Badmin uphold his right to inherit under the will of his partner, the ecologist Elizabeth Walker, who died from cancer in 2010.

Ms Walker, who was 53, and Mr Badmin, had been together since 2005. Her daughters Alison Walker and Jennifer Rowan took Mr Badmin to court to try to overturn the will as he inherited a large part of her estate.

They had tried to argue their mother was in an ‘irrational’ and ‘delusional’ state when she drew up the will that left money to IT analyst Mr Badmin, who was 23 years her junior.

The couple had been introduced through Jennifer Rowan and her husband, with whom Mr Badmin had been friends. Ms Walker and her husband separated in 2007 with Ms Walker leaving the family home in Canterbury to move in with Mr Badmin.

However in 2009 she was diagnosed with a malignant brain tumour, shattering their plans to get married.

Mr Weston, a partner at mfg, worked on the two-week case for four years - one of only a few that gets as far as trial in the High Court.

Judge Nicholas Strauss QC ruled that although Ms Walker’s mental powers had declined considerably by the time she signed the will this had not impaired her ‘testamentary capacity’.

Mr Weston, said: “This was a very sad case, not to mention a very complicated and long-running one. It is rare for cases to go all the way to trial like this.

“This will have an impact on future cases where family members try to suggest that any changes to a will made while someone is terminally ill may not be valid on grounds of mental capacity.

“A will is the way in which someone sets out what they want to happen after they die. Ultimately, what we have been able to prove is that Ms Walker knew precisely what she was doing, despite her illness, when she made her decision to leave most of her fortune to Mr Badmin.”

The case has been reported as a legal authority and has confirmed the relevant test for mental capacity when making a will, or looking to contest a will, is the long established Banks v Goodfellow test of 1870, and not the subsequent test set out in the Mental Capacity Act 2005.