This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.
Q: Passage: One important aspect of the rule-of-law initiatives is the study and analysis of the rule of law's impact on economic development. The rule-of-law movement cannot be fully successful in transitional and developing countries without an answer to the question: does the rule of law matter for economic development or not? Constitutional economics is the study of the compatibility of economic and financial decisions within existing constitutional law frameworks, and such a framework includes government spending on the judiciary, which, in many transitional and developing countries, is completely controlled by the executive. It is useful to distinguish between the two methods of corruption of the judiciary: corruption by the executive branch, in contrast to corruption by private actors. Question: What doctrine seeks to study rules and their relationship with the economy?
A:
Constitutional economics