The sale of cannabis products is illegal in many places of the world, while it is completely legal in other places. Briefly explain the following two scenarios with help of our model on consumer and producer surplus. Supplement your answers whenever appropriate with drawings and illustrations.

a. It is well-known that there is a market for cannabis products even when selling them is illegal. How would you explain this phenomenon? (Hint: Think about analogies to the price ceiling for rental units.)

b. After a complete ban on the sale of cannabis products, one jurisdiction starts to allow their sale. Initially, they do not tax those sales at all. You observe a decrease in the market price of cannabis. Explain this phenomenon.