one of the documented procedures in this installation of the ACS
ug_page_title   page_title   db   group_id   group_name   { show_logo_p "1" }
What it does:
formats the page title for the user group. if show_logo_p is 1, logo will be displayed (given that the logo is enabled for this page), else logo will not be displayed.
Defined in: /web/philip/tcl/user-group-defs.tcl

Source code:

    set selection [ns_db 0or1row $db "
    select decode(logo_enabled_p, 't', 1, 0) as logo_enabled_p, scope from page_logos where scope='group' and group_id=$group_id"]

    if { [empty_string_p $selection] } {
	set logo_viewable_p 0
    } else {
	set logo_viewable_p $logo_enabled_p

    if { $logo_viewable_p } {
	# logo is enabled
	return [ad_decorate_top "<font size=4><b>$group_name</b></font><br><br><font size=4>$page_title"  "<img src=\"/display/get-logo.tcl?[export_url_vars scope group_id]\" ALT=Logo>"]
    } else {

	# logo disabled either by system or group administrator, so return plain text page title
	return "
	<font size=5><b>$group_name</b></font>
	[ad_space 2] 
	<font size=4>$page_title</font>