Here is one way of doing it. This proc is tested in Maya 2009 and 2013.
// switch the tab by name string, note tab must be present
global proc switchAEtoTab(string $name ){
global string $gAETabLayoutName;
string $tabs[] = `tabLayout -q -tabLabelIndex $gAETabLayoutName`;
for ($i=0;$i<size($tabs);$i++){
if ($tabs[$i]==$name)
tabLayout -e -selectTabIndex ($i+1) $gAETabLayoutName;
}
}
Edit: updated script to contain the global name of the tab layout