A jury trying a retired GP who stopped a train heading for the UK’s biggest power station has asked a judge for advice after saying “as a matter of conscience we are finding it difficult to come to a verdict”.

Climate protester Dr Diana Warner, 65, was walking down the railway line outside Drax power station, in North Yorkshire, wearing orange high-visibility clothing and waving an orange flag when a 400-metre long empty freight train stopped on December 14, 2021, Leeds Crown Court has heard.

Warner denies obstructing an engine or carriage using a railway, contrary to the Malicious Damage Act 1861, and a jury of seven men and five women went out to consider its verdict on Tuesday afternoon.

After deliberating for about an hour, the jury came back into court with a note for Judge Guy Kearl KC, the Recorder of Leeds, which said: “As a matter of conscience we are finding it difficult to come to a verdict. What should we do?”

Judge Kearl told the jurors that they should not decide a case based on conscience, telling them they should come to a verdict based on applying the law, defined by him, to the facts of the case, defined by them.

He told them: “You have all taken an oath or affirmation to try this case on the evidence not your conscience. If you are unable to abide by your oath or affirmation you should let me know.”

The judge sent the jurors home and said they will continue their deliberations at 10.30am on Wednesday.

On Monday, Warner told the jury how she went to the railway line near the power station to protest about the plant’s contribution to the climate emergency and deforestation.

She explained that she should have been at court in London that morning, to face proceedings for breaching an injunction to stay off the M25 motorway.

She said this injunction was imposed after she took part in Insulate Britain protests which brought the London orbital motorway to a halt and she told the court she was eventually jailed for two months for contempt of court.

Warner said that she believed the publicity she received from skipping court and stopping the train in North Yorkshire instead, would highlight her campaigning on the climate emergency and other issues.

The jury has seen a video of Warner filmed by the stationary train in which she explains why she believed Drax is the “most ridiculous power station on earth”.

She could be heard explaining how the plant, which burns wood pellets, is “chomping through so many trees”, adding: “We’re just eating our forest, pristine forest.”

The defendant explained her objections to Drax to the jury, saying trees should “never be used to burn for fuel”.

She added: “This is our heritage, our lifeline.”

In his closing speech on Tuesday, prosecutor Oliver Connor told the jury that the only question for them to consider was whether Warner, of Filton Avenue, Filton, Bristol, caused an obstruction.

Mr Connor said: “The common sense conclusion is that stopping the train is obstructing the train.”

In her closing speech, Rosalind Burgin, defending, reminded jurors that the train stopped for less than a minute before it was cleared to continue into the power station, and the incident did not cause any delays nor any costs.

She said: “This whole case is a lot of fuss over an incident that caused no harm to anybody.”