I believe it is essential. Things like "Megan's Law" or the "Amber Alert" wouldn't exist if not for family members getting involved.

A PDF with a collection of many of the September 11th Advocates different press releases from over the years:
http://wewereliedtoabout911.com/wp-content/uploads/2015/02/911advocates.pdf

September 11th Advocates
Comment on the Impending Release of Philip Shenon's Book
The Commission: The Uncensored History of the 9/11 Investigation
February 4, 2008

Philip Shenon's new book, The Commission: The Uncensored History of the 9/11Investigation, serves to justify our suspicions and the concerns of the Family Steering Committee, that we attempted to publicly air during the course of the 9/11 Commission's tenure.

One of the most egregious revelations put forth by Mr. Shenon is the fact that Philip Zelikow was hired as the Executive Director of the 9/11 Commission, despite his direct ties to the Bush Administration. In 2000-2001 he served as a member of Condoleezza Rice's National Security Council (NSC) transition team, where he was allegedly the "architect" of the decision to demote Richard Clarke and his counter terrorism team within the NSC. Furthermore he was a member of the President's Foreign Intelligence Advisory Board (PFIAB) from 2001-2003, where Zelikow drafted most of the 2002 "National Security Strategy of the United States," creating the pre-emptive Iraq war strategy. These areas were within the scope of the Commission's mandate and as such were of critical importance to determine what, if any, impact they had on the government's ability to prevent the 9/11 attacks.

As the Executive Director of the 9/11 Commission, Philip Zelikow was given the responsibility for choosing the entire direction of the Commission's investigation. Essentially, Mr. Zelikow determined who was or was not interviewed as a witness, and which information was or was not looked at. He also influenced which documents would be requested from the various agencies. It seemed to us, that allowing an individual with this much involvement in the Bush administration to run the investigation, might give the appearance of impropriety and could ultimately taint the Commission's findings.

In a statement issued by the Family Steering Committee of March 20, 2004 we wrote:

It is apparent that Dr. Zelikow should never have been permitted to be Executive Staff Director of the Commission. As Executive Staff Director, his job has been to steer the direction of the Commission's investigation, an investigation whose mandate includes understanding why the Bush Administration failed to prioritize the Al Qaeda threat.

In the same statement we also called for:

Zelikow's immediate resignation; Zelikow's testimony in public and under oath; and the subpoena of Zelikow's notes from the intelligence briefings he attended with Richard Clarke.

Commission Chairman Tom Kean and Vice-Chair Lee Hamilton instead chose to have Mr. Zelikow recuse himself from the areas of the investigation that dealt with the transition period. However, they allowed Mr. Zelikow to be one of only two people (Ms. Gorelick was the other) to review the Presidential Daily Briefings (PDB's), reports that went to the heart of what the White House and its National Security Advisor, Condoleezza Rice, knew prior to 9/11. While investigating the events that led up to the September 11th attacks, Philip Zelikow was called as a witness by the 9/11 Commission though transcripts of his testimony were never made public.

From an email sent to me.

September 11th Advocates
Regarding Declassification and Release of Documents
June 18, 2007

The Public's Right to Know - Declassification and Release of Documents petition (http://www.petitiononline.com/july10/petition.html ) surpassed 15,000 signatures. As promised, we have hand delivered it to lawmakers in Washington, DC.

UPDATE