Crime blogger Steve Huff weighs in on Charles Lee "Cookie" Thornton in a thorough blog post. He prominently notes the First Amendment Center article referenced in the previous blog post, but also tracks down previous instances of Thornton's disruptive actions.
Among them includes a restraining order Thornton filed against the city (found here), a reference to Thornton's presence in the minutes of a 2007 city council meeting and, perhaps most interestingly, an attempt by Thornton to run for Kirkwood City Council. Huff states:
According to the archives of the St. Louis Post-Dispatch, Thornton even had minor political ambitions of his own at one point. A list of "Candidates seeking Mayoral seats, spots as trustees, aldermen," and "council members" published on February 14, 1994 listed "Charles "Cookie" Thornton, 351 Attucks Street" as a candidate for one of the three seats then open on the Kirkwood City Council.
(According to an April 6, 1994, article published in the Post-Dispatch, Thornton came in last place in the election, earning 2334 votes.)
Elsewhere, here's a link to all of the court documents associated with Thornton's recent complaint against the city of Kirkwood. Filed on January 18, 2007, the complaint -- in the amount of $350 -- was dismissed on January 28, 2008.
Finally, Crime Scene KC also has a comprehensive post about the shootings, including links to local blog reactions and a commenter who claims that Thornton allegedly accrued $18,000 in parking tickets in three years.