First point - Article 237 of our Code of Organization and Civil Procedure reads as follows: “A judgment shall not operate to the prejudice of any person who neither personally nor through the person under whom he claims nor through his lawful agent was party to the cause determined by such judgment." This is the res inter alios acta rule. In this context, it might be useful not to confuse a case to declare a law unconstitutional (typically, using Article 116) with a case to declare a judgment null due to it not being in line with the Constitution.
Second point - Having said the above, we had, in the past, conflicting judgments where at one point, the Constitutional court declared a law as being unconstitutional whereas at a later point, it did not. The obvious question to ask is: which is the correct position?
Third point - Thankfully, the Constitution itself gives Parliament the right to make and unmake laws, which it has made, by abrogating repealing or revoking them. In other words, the Constitutional Court can declare a law to be invalid but it cannot abrogate, repeal or revoke any law.
Finally, if Parliament does not live up to people's expectations and unmake the 'bad laws', it is for the electorate to unmake those parliamentarians.