Modifying response object in Controller Plugin

<?php

class Application_Model_AuthPlugin extends Zend_Controller_Plugin_Abstract
{
    public function preDispatch(Zend_Controller_Request_Abstract $request)
    {
        $protectedModules = array ('member');
        if (in_array($request->getModuleName(), $protectedModules)) {
            if (!Zend_Auth::getInstance()->hasIdentity()) {
                $this->getResponse()->setRedirect('/auth/index');
            }
        }
    }
}