Maybe the problem lies with the definition of legal certainty itself. Does this mean that the law should be predictable? Or does it mean that the law should be formal and rigid, that there is a general standard applicable for every cases and that it should be enforced without any exception? Answering this issue is indeed a herculean task but I'll try to describe my basic points in this post to start the discussion.
First, we should move to a famous Antitrust Case in the Supreme Court of the United States, Leegin Creative Leather Product, Inc. v. PSKS, Inc. This was a case for vertical price fixing, where Leegin, a leather goods and accessories manufacturer imposed a minimum fixed price for its products that must be complied by its retailers. One of its retailers, PSKS, refused to comply with such minimum price and as result, Leegin ceased to sell its products to PSKS imposing a huge amount of losses to PSKS. PSKS then argued that Leegin has entered into an agreement with his retailers, including PSKS, that restrained trade or commerce (basically restricting competition) and therefore it should be deemed violating the Sherman Act (the Antitrust Law of the United States).
For more than 100 years, the precedent in the United States concerning vertical price fixing is that it is a per se illegal agreement, meaning whatever the reasoning for entering into such agreement, such agreement will be deemed as anti competitive and therefore illegal. However the majority opinion in the Supreme Court reverse such long standing precedent as instead declare the rule as a rule of reason, meaning that such agreement will only be illegal if there is a solid evidence that such agreement is unreasonable and causes anti competitive behavior which adversely affect the welfare of the society.
This is a very interesting case for many reasons. First, the decision was full with economic analysis (something that is quite rare on the Supreme Court level). Two, the decision rejected the application of per se rule for this type of case (which is the usual formalistic way of legal reasoning) on the basis that while such per se rule lowers the administrative costs for future cases (i.e. since every similar contract should be deemed illegal, it can be expected that all courts in the United States will give similar treatment without having to go to a lengthy process caused by the use of rule of reason), it can also produce inefficient results since in the view of the majority, the existence of vertical price fixing can also produce pro-competitive results in certain conditions (such as promoting competition between manufacturers while maintaining price in the level of retailers).
The dissenting itself argued that while there might be certain positive economics effects of vertical price fixing, this is not something unknown back in 1911. If the past justices believed that such positive elements can not justify the legality of the arrangement, how could the current justices defy such reasoning? If there is no significant change in the conditions related to the case, the stare decisis rule (i.e. that a court precedent should be binding against future cases which have similar conditions and elements) should still be applicable and therefore the court should not reverse the precedent. This will ultimately jeopardize legal certainty created by stare decisis rule. As you can see, both groups of justices provide interesting points with respect to legal certainty versus legal flexibility (which is supported by economic reasoning).
Another experience that I had with my Judicial Decision Making course is also interesting to be shared here. As justices in the Supreme Court of Delaware, we handle various cases related to mergers and takeovers of publicly listed corporations. The issues are complex, ranging from shareholders rights for appraisal for their shares in a merger transaction, conflict of interests between shareholders and directors, and fiduciary duty of directors toward corporations. We work on the basis of clean slate doctrine (so we can build our own business law doctrine) and we also build our own set of precedents to be used for future cases.
Only in three weeks and 6 cases, I could easily see how difficult it is to build a consistent approach to the various issues that we face. When we think we have already considered everything, the next new cases show that the principle that we used in the previous case cannot be applied consistently or it will bring a perverse result, either to the corporation or to the shareholders, etc. To certain extent, we need to revise the precedent that we have established previously in order to accommodate the cases.
Take as a case, the doctrine of business judgment, that directors should not be liable to the shareholders in case they can show that they have done their job with good faith and with a reasonable care. Seems easy to translate in practice, but in reality it is not. When can we say that the directors have acted to the best extent of their capabilities? Who can evaluate the performance of the directors? The court? But the court is not a business expert, and putting too much standard might not be a good solution if the ones who create such standard do not have sufficient capacity. So again I face a dilemma, picking certainty versus uncertainty.
If only all legal issues are white and black, maybe seeking legal certainty would not be a desperate issue. But in reality, we live in a gray world. Forcing certainty to everything tends not to solve the problem. On the other hand, having an exact rule will reduce administrative costs (as stated in Leegin case), but on the other hand, it does not mean that it is clean from other type of costs, in fact it can also produce inefficient results. The key question is, how can we strive for a balance?
One of the interesting point of the US legal system is how they divide their laws into two major groups. The common law and the statutory law. The statutory law resembles the civil legal system that we use in our country where everything is regulated by statutes and we tend to answer any legal issues on the basis of the provisions of such statutes. Meanwhile, the common law also use statutes as the basis (other than using judge made law), however statutory provisions that fall under the common law group tend to be more general and somewhat ambiguous, which most or the time are further elaborated by the judges in the court. The US Antitrust Law and the Securities Laws are two good examples of this common law type where the provisions are simple and open to many interpretations by the court.
Obviously the level of certainty in this type of common law statutes is lower than the statutes in the statutory law group. I can confirm this at least from my experience dealing with US securities laws and antitrust law issues. You can make various arguments with the issues such as what constitutes securities, what constitutes public offering, what constitutes a rule of reason case, etc. Compared this with Indonesian securities laws and antitrust laws where it is more certain in terms of definition and concepts. Even for the Delaware General Corporate Law which is quite exhaustive, we can have a heated debate concerning what provisions should be considered as a default rule (i.e. can be waived by parties through a contract like in Indonesian contract law) and what provisions should be considered as a mandatory rule absent express provisions in the body of the law.
Maybe this is a good time to evaluate to what extent we should have certainty in our legal system, whether everything should be regulated precisely so that there is no room for flexibility for the sake of securing certainty. We should also see to what extent the court can be a more productive asset in our legal system by giving them bigger flexibility in solving certain type of cases (such as in corporate and securities laws).
Furthermore, instead of trying to regulate everything within the provisions of a law, maybe it would be a good idea to instead create a more flexible regulation accompanied with a governing value that should be used whenever we want to interpret and enforce the provisions of such regulation. One good example is the normative principle of law and economics where law should be designed to promote efficiency and maximize the welfare of the society (though other people might also have different values). I believe that answering this issue would contribute significantly to the development of our legal scholarship and I would be interested to elaborate more my ideas on this subject in a more formal way.