A Huddersfield man who played a leading role in the importation and distribution of substantial amounts of MCAT has been jailed for eight years.

Jurors at Bradford Crown Court found 49-year-old Derrick Smith guilty of conspiracy to import the Class B drug from China and the Far East and a judge said it was clear that the defendant and an another man had been running “a highly profitable and successful business”.

Father-of-three Smith, of Keldregate, Bradley, was also found guilty of conspiracy to the supply the MCAT between March 2012 and March 2013.

Judge Peter Benson said it was an aggravating feature of the case that he had misled a wholly innocent Bradford woman into packaging the drugs for him into DVD cases which were then distributed to customers in this country and around the world.

The jury cleared 51-year-old Helen Brookes on both of the conspiracy charges and Judge Benson said Smith had used her to distance himself from the offending.

The judge highlighted the fact that when police raided Brookes’ home they seized more than a kilogram of MCAT together with DVD cases and Jiffy bags.

Judge Benson said when police searched Smith’s home there was “not a trace” of the drugs operation and he refused to disclose passwords which would have given investigating officers access to his computer.

“That computer would have shown the exact scale of your operation, but there is no doubt in my mind that for a period of at least a year you were involved in the importation and distribution of this controlled drug,” the judge told Smith.

“You knew full well what you were doing...and you exploited someone who trusted you to assist you and also to distance yourself from the operation.”

Brookes told the jury that Smith dragged her into the operation when she was short of money and she believed that the white powder was plant food.

Smith claimed that his male accomplice had said the business was involved in supplying so-called “legal highs”.

He accepted that he had been receiving frequent parcels of stock from his male accomplice and that they contained between one and two kilograms of the drug.

Judge Benson said Smith, who had never served a prison sentence before, had played a leading role in the operation.

“It’s clear from the documentation that we do have in this case that there must have been dealings in very substantial and significant quantities (of drugs),” he added.