I think interpretation is inevitable. The law is not like science, where there's an objective reality that can be measured and accurately defined. It's about principles, and interpretation. That the nine theoretically most brilliant lawyers in the land can end up utterly at odds 5-4 over the same issue exemplifies how interpretation can vary. We can also consider that Supreme Courts can and have effectively overturned older Supreme Court rulings, or applied very different principles to come to a different conclusion on a similar if not near-identical matter.
Fundamentally, the law is about the orderly and effectively running of societal rules, thus society itself. If the law is not achieving that, there's a problem. The base responsibility for making laws lies with the legislature, but given that interpretation is inherent, I think the judiciary also has a mandate to interpret law in a constructive fashion for the good of society. If the judiciary can make a decision that will have a clearly, severely damaging effect on society or a great number of people, I think they have a responsibility to consider their decision carefully, because it goes against a lot of the basic point of the law. I almost dread to use the term given its vague meaning and flaws, but "common sense" matters.
If we think about principles, I think lynching (usually black) people for the societal satisfaction a racist, ruling white clique offends deep, fundamental US principles of what society (and thus the law) is supposed to achieve, like a right to life, equal treatment before the law, etc. However, let's say that cotton thieves are beginning to become a massive problem, so cotton thieves all get a 10-stretch to make an example of them, when roughly equivalent thievery of other things gets only 5. This offends somewhat against equality before the law, but it's still within major fundamental principles, sentencing guidelines, and may theoretically be societally useful to dampen down a specific problem.
I would suggest another principle is the idea that the government has the mandate to make law. Take a massive, major policy act. I would suggest the role of the courts would generally be to facilitate legislation unless it is clearly illegal or otherwise offends a fundamental principle, because otherwise the courts start usurping governance. If the courts are refusing legislation on what appear to be controversial, tangential or weak reasoning, I think that's getting problematic.