- In US, this problem dealt with in Constitution: Art 1 para 3
- Taken alone, retro rules are a monstrosity.
- To appraise them intelligently, we must place them in the context of a system of rules that are generally prospective. Curiously, then, situations ay arise where retro rules essential to advance cause for legality. More info at Dentist Calgary
- When? – when things go wrong that retro statute often becomes indispensable as a curative measure for internal morality. “Though proper movement is forward, sometimes we have to turn back and pick up the pieces”.
- And: though taken by itself, retro impairs principle of legality, but it alleviate effect of a previous failure to realise two other desiderata of legality: that the laws should be made known to those affected by them and that they should be capable of being obeyed.
- Don’t be fooled, retro not always curative, e.g Roehm Purge, killed 100 ppl, then Hitler made retroactive statute.
- Second perspective is not so much contribution retro makes to inner morality of law, but rather to circumstance that it unavoidably attaches in some measure to the office of judge.
- How? If A and B both have equally good claim on face of statute, and judge decides the case, he is inevitably engaging in an act of retrospective legislation.
- Also, consider that after A v B decided, C and D have dispute and C refuses to settle because he thinks A v B decision was wrong and that it should be overruled. If overruling is made retrospective, then D loses out though he relied on a legal decision that was clearly in his favour.
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