diff --git a/cas-client-core/src/main/java/org/jasig/cas/client/validation/AbstractTicketValidationFilter.java b/cas-client-core/src/main/java/org/jasig/cas/client/validation/AbstractTicketValidationFilter.java
index d712713..4556bb9 100644
--- a/cas-client-core/src/main/java/org/jasig/cas/client/validation/AbstractTicketValidationFilter.java
+++ b/cas-client-core/src/main/java/org/jasig/cas/client/validation/AbstractTicketValidationFilter.java
@@ -194,6 +194,8 @@ public abstract class AbstractTicketValidationFilter extends AbstractCasFilter {
                     throw new ServletException(e);
                 }
 
+                response.sendError(HttpServletResponse.SC_FORBIDDEN);
+
                 return;
             }
         }