Tracy Cameron told the BBC her son, Grant, and two other London residents were subjected to electric shocks administered by police after their arrest in August for drug possession and intent to traffic.
"Your son being arrested so far away from home is challenge enough to deal with but, once he told us how he'd been treated, I can only describe it as something from a horror story," she said.
A judge will deliver the verdict in the case Monday, the BBC said. Grant Cameron, along with Karl Williams and Suneet Jeerh, were accused of having a quantity of synthetic marijuana in their car while on vacation in the UAE.
Tracy Cameron said the trio were pushed into signing Arabic-language confessions after being roughed up by police in their hotel room.