A woman who says her marriage is “loveless and desperately unhappy” is trying to persuade Supreme Court justices to let her divorce her husband of 40 years.
Five justices are analysing Tini Owens’ case at a hearing in London. They are not expected to produce a ruling until later in the year.
Lawyers say the case could have implications for unhappily married people.
Mrs Owens, 68, has already lost two rounds of her legal battle.
In 2016 she failed to persuade a family court judge to allow her to divorce retired 80-year-old businessman Hugh Owens, who does not want to divorce.
Last year three appeal judges ruled against her after a Court of Appeal hearing in London.
They said Mrs Owens had failed to establish that her marriage had, legally, irretrievably broken down and dismissed her challenge to a ruling by Judge Robin Tolson.
One appeal judge said she had reached her conclusion with “no enthusiasm whatsoever” but said Parliament would have to decide whether to introduce “no fault” divorce on demand.
Another said Parliament had “decreed” that being in a “wretchedly unhappy marriage” was not a ground for divorce.
Mrs Owens’ lawyers say she should not have to prove that Mr Owens’ behaviour has been “unreasonable” – only that she should not “reasonably be expected” to remain with him.
They say the case is about “proper interpretation” of legislation.
Barrister Philip Marshall QC, who leads Mrs Owens’ legal team, told justices that a “modest shift” of focus in interpretation of legislation was required.
Judges have heard how Mr and Mrs Owens had married in 1978 and lived in Broadway, Worcestershire.
She petitioned for divorce in 2015 after moving out.
Mrs Owens said her husband had behaved unreasonably and argued that the marriage had broken down.
Mr Owens disagreed and denied allegations made against him.
He was against a divorce and said they still had a “few years” to enjoy.