Gleision trial: 'Crucial factual dispute' key to case
The case against a mine manager accused of manslaughter over the deaths of four miners who drowned rests on a "crucial factual dispute", a court heard.
The men died in Gleision drift mine near Pontardawe in the Swansea Valley in 2011.
Malcolm Fyfield and pit owners MNS Mining Ltd deny gross negligence.
Summing up the case at Swansea Crown Court, Mr Justice Wyn Williams said the prosecution had to prove Mr Fyfield did not inspect the mine as he said he did.
The trial has heard Charles Breslin, 62, David Powell, 50, Philip Hill, 44, and Garry Jenkins, 39, died when 650,000 gallons of water poured into the mine after they blasted into old coal workings.
Mr Fyfield, 58, who had come out of retirement to run the mine, had been given orders to connect two parts of the pit to improve ventilation.
The prosecution claims he should have known his workers would be breaking through an area called a "cautionary zone" where underground water was present.
But the defence said the case was "fundamentally flawed".
Mr Justice Williams told jurors on Tuesday: "It is for the prosecution to make you sure that he did not inspect as he said he did.
"If the prosecution has not convinced you... Mr Fyfield and MNS cannot be found guilty.
"In that scenario both are entitled to be found not guilty of every count."
Mr Justice Williams said if that was the decision of the jury it would not be necessary for them to consider any of the rest of the evidence heard during the three month-long trial.
He said this "crucial factual dispute" went to the heart of the case against Mr Fyfield.
The judge said even if the jury concluded that Mr Fyfield had made mistakes, even very serious ones, or errors of judgement, that would not amount to gross negligence.
The negligence would have to be flagrant, exceptionally bad, for his conduct to amount to gross negligence, the court was told.
Mr Justice Williams will conclude his summing up on Thursday and the jury will retire to begin considering verdicts later that same day.
Mr Fyfield denies four counts of manslaughter through gross negligence. MNS Mining has pleaded not guilty to four counts of corporate manslaughter through gross negligence.
The trial continues.