Failed "perfect crime": Husband plants drugs on wife, goes to prison instead

[Brainspore]

@EllsworthToohey

a plan that could have led to her facing the death penalty.
[…] Under Singapore’s Misuse of Drugs Act, he could have faced up to 10 years in prison or a fine of up to S$20,000.

Why was his maximum potential punishment less than the punishment she could have faced had his plan succeeded?