Index: lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/service/AssessmentServiceImpl.java
===================================================================
diff -u -r1ed7aff27284aa7bc7e665fb9262ced86bc0f758 -rc93c1eaabb8c79d6f2bb3f31872e262e52e271af
--- lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/service/AssessmentServiceImpl.java	(.../AssessmentServiceImpl.java)	(revision 1ed7aff27284aa7bc7e665fb9262ced86bc0f758)
+++ lams_tool_assessment/src/java/org/lamsfoundation/lams/tool/assessment/service/AssessmentServiceImpl.java	(.../AssessmentServiceImpl.java)	(revision c93c1eaabb8c79d6f2bb3f31872e262e52e271af)
@@ -1744,6 +1744,10 @@
 		    assessmentDao.removeObject(NotebookEntry.class, entry.getUid());
 		}
 
+		if (session.getGroupLeader() != null && session.getGroupLeader().getUid().equals(user.getUid())) {
+		    session.setGroupLeader(null);
+		}
+
 		// propagade changes to Gradebook
 		gradebookService.updateActivityMark(null, null, userId, session.getSessionId(), false);
 
Index: lams_tool_lamc/src/java/org/lamsfoundation/lams/tool/mc/service/McServicePOJO.java
===================================================================
diff -u -r351836c805d1e36ba77baf154d72e7e934975341 -rc93c1eaabb8c79d6f2bb3f31872e262e52e271af
--- lams_tool_lamc/src/java/org/lamsfoundation/lams/tool/mc/service/McServicePOJO.java	(.../McServicePOJO.java)	(revision 351836c805d1e36ba77baf154d72e7e934975341)
+++ lams_tool_lamc/src/java/org/lamsfoundation/lams/tool/mc/service/McServicePOJO.java	(.../McServicePOJO.java)	(revision c93c1eaabb8c79d6f2bb3f31872e262e52e271af)
@@ -1293,6 +1293,10 @@
 			mcContentDAO.delete(entry);
 		    }
 
+		    if (session.getGroupLeader() != null && session.getGroupLeader().getUid().equals(user.getUid())) {
+			session.setGroupLeader(null);
+		    }
+
 		    mcUserDAO.removeMcUser(user);
 
 		    gradebookService.updateActivityMark(null, null, userId, session.getMcSessionId(), false);
Index: lams_tool_laqa/src/java/org/lamsfoundation/lams/tool/qa/service/QaServicePOJO.java
===================================================================
diff -u -rd09e2d4b292439539e658d6f19bb4807123ad9a9 -rc93c1eaabb8c79d6f2bb3f31872e262e52e271af
--- lams_tool_laqa/src/java/org/lamsfoundation/lams/tool/qa/service/QaServicePOJO.java	(.../QaServicePOJO.java)	(revision d09e2d4b292439539e658d6f19bb4807123ad9a9)
+++ lams_tool_laqa/src/java/org/lamsfoundation/lams/tool/qa/service/QaServicePOJO.java	(.../QaServicePOJO.java)	(revision c93c1eaabb8c79d6f2bb3f31872e262e52e271af)
@@ -602,6 +602,10 @@
 			qaUsrRespDAO.removeUserResponse(response);
 		    }
 
+		    if (session.getGroupLeader() != null && session.getGroupLeader().getUid().equals(user.getUid())) {
+			session.setGroupLeader(null);
+		    }
+
 		    qaQueUsrDAO.deleteQaQueUsr(user);
 
 		    NotebookEntry entry = getEntry(session.getQaSessionId(), CoreNotebookConstants.NOTEBOOK_TOOL,
Index: lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/service/ScratchieServiceImpl.java
===================================================================
diff -u -reb056585fef20d548c58cf015845317c7aae33c0 -rc93c1eaabb8c79d6f2bb3f31872e262e52e271af
--- lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/service/ScratchieServiceImpl.java	(.../ScratchieServiceImpl.java)	(revision eb056585fef20d548c58cf015845317c7aae33c0)
+++ lams_tool_scratchie/src/java/org/lamsfoundation/lams/tool/scratchie/service/ScratchieServiceImpl.java	(.../ScratchieServiceImpl.java)	(revision c93c1eaabb8c79d6f2bb3f31872e262e52e271af)
@@ -1801,6 +1801,10 @@
 		    scratchieDao.removeObject(NotebookEntry.class, entry.getUid());
 		}
 
+		if (session.getGroupLeader() != null && session.getGroupLeader().getUid().equals(user.getUid())) {
+		    session.setGroupLeader(null);
+		}
+
 		scratchieUserDao.removeObject(ScratchieUser.class, user.getUid());
 
 		gradebookService.updateActivityMark(null, null, userId, session.getSessionId(), false);