Some view the State Comptroller's Office as a separate estate - the investigative branch. But last week it became clear that the investigative branch is actually situated at the Knesset building in Givat Ram. During the course of last week, the final one of its summer session, the Knesset appointed no fewer than four new committees of inquiry, bringing the total for the year to seven. It thereby evinced an investigative activism that can even compete with the legislative activism of the Supreme Court in the Shamgar-Barak days.

Until recently the Knesset State Control Committee had a dignified and restrained record. In the 50 years the State Comptroller Law has existed, the committee exploited its authority to establish a commission of inquiry only once, in 1985 - the Beiski Commission on the bank shares crisis. This past year, since National Religious Party chairman Zevulun Orlev was appointed committee chairman, it has established no fewer than three state commissions of inquiry, two of them in the last week: a panel to review the treatment of Holocaust survivors, a panel to probe the water crisis, and a panel to look into the handling of Gush Katif evacuees. Each of these subjects is important. Not one of them even barely warrants a state commission of inquiry.

But the State Control Committee is not alone in seeking to investigate the country to death. The Knesset plenum has set up no fewer than four parliamentary committees of inquiry in recent months. First, MK Ahmed Tibi (Ra'am-Ta'al) succeeded in getting a committee established to examine the state of Arab employment in the civil service. Then, MK Moshe Gafni (United Torah Judaism) set up a committee to find out how the gravesite of Shimon bar Yochai is doing. Last week the Knesset established one investigative panel on the conduct of the Claims Conference, and another on the bungled treatment of Ethiopian immigrants. A veritable investigations department.

And note how the committees divide evenly among sectors. There's a committee for the Arabs, one for the radical right, a committee for the ultra-Orthodox, and one for the Ethiopians, and two committees for the Holocaust survivors. Some countries set up national reconciliation committee. We set up committees to perpetuate rifts and conflict.

Orlev claims he decided to establish the commissions of inquiry after trying every other way to bring about change. But a commission of inquiry, especially a state one, is not a type of demonstration and is not a means of protest. A state commission of inquiry is a means to ascertain the circumstances that led to a national trauma. Orlev's commissions therefore constitute a severe devaluation of the concept.

Up to 20 years ago, the Supreme Court was an institution that enjoyed a broad consensus and was acceptable to all. Its power eroded when it was called upon to rule on every controversial issue. Now, with the Supreme Court pummeled black and blue, the Knesset is also endangering the standing of commissions of inquiry.

This week Knesset members crossed the 4,000-bill line. Most will never make it to the discussion phase or a vote. Even the MKs term a large share of these bills "legislative declarations." Now they are putting the commissions of inquiry through a similar devaluation process, and turning them into investigative declarations.

Establishing a commission of inquiry is not intended only to be a quest for the truth, but is in itself the verdict. There has yet to be born a commission of inquiry whose members, after spending hundreds of hours at a cost of millions of shekels and consuming hundreds of kilos of bourekas, then announce: "Sorry, you made a mistake. You appointed us in vain. There are problems and failings here that need to be fixed, but there definitely has not been a debacle." By its very nature, a commission of inquiry finds "debacles."

The truth is, of course, that when a commission of inquiry is set up in Israel, nobody has any interest in scholarly conclusions, lessons to be drawn, problems to be corrected. The sole test for a commission of inquiry is whether it orders heads to roll. The head-rolling orders are submitted, in turn, to two tests: how high they aim and how tough they are. So it is not the correction of failings that we seek, but rather some sort of momentary purification by means of a public exorcism ritual.

A way ought to have been found to nullify all four of the inquiry panels the Knesset set up last week, and thereby save dozens of jobs and who knows how many millions of shekels. But even if that is impossible, the first conclusion from the work of these committees can be stated in advance: The power of the State Control Committee to establish commissions of inquiry must be curtailed, and additional authorization required - that of the Knesset plenum or House Committee.