Answer: The principle of demand states that as the PRICE of a good, service or commodity increases, the DEMAND decreases.
For example, a consumer will likely buy two loaves of bread for $50, than one loaf for $40.
To the question, if all crimes sentences were doubled, ( increase in the price of good) the crime rate will decrease ( demand for crimes). This in essence will discourage from committing crimes, thereby making prisons less crowded. In conclusion, based on the concept of demand, this argument is incorrect.