The 31-year-old nephew of the Earl Cawdor is facing allegations he smuggled nearly 100kg of cocaine in Kenya.
Jack Marrian is said to have smuggled the class A drug into Mombasa port, hidden in a consignment of sugar from Brazil which was going to his company Mshale Commodities, which is headquartered in Uganda.
But Mr Marrian could be exonerated after it was reported that the head of Kenya’s anti drugs unit has failed to disclose key evidence.
The drugs were discovered inside a container filled with 509 bags of sugar.
They were shown to Mr Marrian’s trial at the Criminal Investigation Department (CID) headquarters.
The court heard that the case’s lead investigator, Hamisi Massa, had received letters from authorities in America and Spain which said that a criminal gang was trying to get the drugs off the ship in Valencia, which was the ship’s first port of call.
However, defence lawyers acting for both Mr Marrian and Kenyan Roy Mwanthi, who is accused of smuggling alongside him, said they had received no details of the letter.
Acting for Mr Marrian, Andrew Wandabwa told the court that he understood intelligence reports had already indicated that the Kenyan police had the wrong people.
Magistrate Derrick Kutto, presiding over the case, has now ordered officers to hand over all evidence within 15 days. He stressed the importance of the defence team receiving all relevant information, saying: “The liberty of the accused is at stake.”
Mr Hamisi said he had received information in July about a suspect container which was bound for Mombasa.
Ninety slabs of cocaine had been concealed along with the cargo. Each slab was wrapped with plastic bags with the logo of French sportswear designer Lacoste on them.
He said that once the drugs were found, he served notice to ship owners the Mediterranean Shipping Company that their vessel had been seized.
Within days, he had arrested Mr Marrian and Mr Mwanthi, although both vigorously deny the charges brought against them.
Their defence teams say the most likely scenario is that a cartel had placed their illegal cargo inside a legal consignment being shipped by Mr Marrian.
Mr Marrian is the son of a British aristocrat whose family owns Cawdor Castle, the home of Shakespeare’s Macbeth.
He also went to the same school as the Duchess of Cambridge, although he was three school years behind her at the £30,000-a-year Marlborough College.