Shrien Dewani has been found not guilty of plotting the murder of his wife Anni Hindocha while on honeymoon in South Africa.
Judge Jeanette Traverso dismissed the case after there was "insufficient evidence" for the state to continue.
Traverso ruled the evidence in this case "fell below the threshold" for a reasonable court to make a conviction.
She described the evidence of taxi driver Zola Tongo, the only witness linking Dewani, as "so improbable", that "one cannot see where the lies end and the truth begins".
In her conclusion, the only reason not to grant the application would be out of hope the accused would implicate himself if he stood trial.
She announced at Western Cape High Court, in South Africa: "I am making the following order... the application is granted. The accused is found not guilty on this charge."
She added, however, hotel worker, Monde Mbolombo, would not have indemnity from prosecution after playing a 'middle man' role in the murder.
He admitted in court to putting Tongo in touch with Mziwamadoda Qwabe and gunman Xolile Mngeni, who carried out the killing in Gugulethu, near Cape Town on 13 November 2010.
Dewani appeared to show little emotion as he heard the case against him was being dismissed while the family of his wife looked devastated at the judge's ruling.
Speaking outside court, her sister Ami Denborg said: "We came here for the truth, seeking answers but are left with so many unanswered questions, it's a very sad day.
"The knowledge of not knowing what happened to my dearest little sister... will be with my family for the rest of our lives.
"We hope no other family will ever have to go though what we have been through."
Mngeni was sentenced for life for Hindocha's murder in 19 November, 2012. He died in jail in October after suffering a brain tumour.
Qwabe was jailed for 25 years in August, 2012, after pleading guilty to the murder and Tongo was given 18 years on 7 December, in 2010 after admitting his role in the killing.