Can I give my personal opinion here ?
While I apreciate Xahar a lot personally and would really like to see him holding this office and put an end to the PCP's political machine here, I can't honestly support him in this court case. Invoking regional rights to limit the power of Supreme Court's decisions would be a dangerous precedent, creating a partial impunity for anyone who commits a crime. Sorry to say that.
The case here is not to limit the power of the Supreme Court's decisions - their power is and has always been to interpret the law and make decisions accordingly, and that power will not change even if they rule in the plaintiff's favor. The Senate's ability to make new laws is what will ultimately be affected.
Furthermore, your argument is not a legal one. A law may be unconstitutional regardless of its merit. If a law that would be unconstitutional is found to be necessary, there are means by which it can be made constitutional. In this case, either passing an amendment or regional extensions of the law would be sufficient.
This is how the system is supposed to work, right ? Now, if the Supreme Court agrees with Xahar in considering that banning someone from regional offices for a federal is unconstitutionnal, the power of the Supreme Court wil
de facto be weakened, enforcing the criminals' impunity.
I know that it's an interpretation issue, and the Constitution's statement can be interpreted in both ways, both making sense constitutionnally. I just wanted to warn justices about the possible consequences of their decision.