Another Case for Constitutionalism

I grow weary of reading the inane claptrap that qualifies as news in Israeli newspapers nowadays: "Many overweight Israelis are in denial, poll shows", or "When Israel stars in U.S. campaigns – is it good for the Jews?" Tedious and bothersome, in my opinion. But what really got my goat in today's Haaretz was the unnecessary huffing by Professor Menachem Mautner of Tel Aviv University over why the Israeli Supreme Court is considered a left-wing institution.
He explains that both right- and left-wing parties file petitions to the court over political grievances and, because the left-wing parties typically construct an argument rather than claim personal harm, the court overwhelmingly rules in their favor. His solution to this perceived bias is that 

"The High Court should understand that these petitions inflict serious harm (how precisely, Mautner does not say). It should change its doctrine regarding the right to a hearing and turn away MKs seeking that it adjudicate political matters." 

No, Professor Mautner. You may be right that the Supreme Court should not be deliberating in political arguments, but you are wrong in suggesting they change their policy. 
What is absolutely necessary is a constitution that clearly delineates the Supreme Court's role in the political process. "If [an MK] claims that a personal right of his has been violated (by the Knesset speaker or the attorney general, for example ) he should be able to petition like anyone else. But when an MK wants the court to rule on a political matter, the court should reject the petition," Mautner argues. Professor Mautner, the problem lies not in the Court's policy, but in the excess of "should" in legal procedure. For this reason all other states (with the notable but explicable exception of the UK) have a constitutional document delineating the manner and methods of such matters. 
Thank you, Professor Mautner, for inadvertently making an yet another argument for Israeli constitutionalism.