diff --git a/source/java/org/alfresco/repo/security/authority/AuthorityServiceImpl.java b/source/java/org/alfresco/repo/security/authority/AuthorityServiceImpl.java
index 34a3033da1..9f20145637 100644
--- a/source/java/org/alfresco/repo/security/authority/AuthorityServiceImpl.java
+++ b/source/java/org/alfresco/repo/security/authority/AuthorityServiceImpl.java
@@ -606,7 +606,13 @@ public class AuthorityServiceImpl implements AuthorityService, InitializingBean
     {
         checkTypeIsMutable(type);
         String name = getName(type, shortName);
-        authorityDAO.createAuthority(name, authorityDisplayName, authorityZones);
+
+        //MNT-9794 fix. If authority with 'name' doesn't exist it will be created
+        if (!authorityDAO.authorityExists(name))
+        {
+            authorityDAO.createAuthority(name, authorityDisplayName, authorityZones);
+        }
+
         return name;
     }
     
diff --git a/source/test-java/org/alfresco/repo/security/authority/AuthorityServiceTest.java b/source/test-java/org/alfresco/repo/security/authority/AuthorityServiceTest.java
index b23ee87f58..b33fa9172b 100644
--- a/source/test-java/org/alfresco/repo/security/authority/AuthorityServiceTest.java
+++ b/source/test-java/org/alfresco/repo/security/authority/AuthorityServiceTest.java
@@ -591,6 +591,34 @@ public class AuthorityServiceTest extends TestCase
         pubAuthorityService.deleteAuthority(auth1);
         assertEquals(0, getAllAuthorities(AuthorityType.ROLE).size());
         assertEquals(0, pubAuthorityService.getAllRootAuthorities(AuthorityType.ROLE).size());
+
+        // Testing MNT-9794 fix.  Creates authority 'DUPLICATEDGROUP' twice. Only one authority with such name should be created.
+        String dublicatedAuthorityShortName = "DUPLICATEDGROUP";
+        AuthorityType dublicatedAuthorityType = AuthorityType.GROUP;
+
+        //Creates authority twice with duplicated name
+        pubAuthorityService.createAuthority(dublicatedAuthorityType, dublicatedAuthorityShortName);
+        pubAuthorityService.createAuthority(dublicatedAuthorityType, dublicatedAuthorityShortName);
+
+        List<String> duplicatedGroupAuthorities = getAuthorityByTypeAndShortName(dublicatedAuthorityType, dublicatedAuthorityShortName);
+
+        //Only one authority should be created with duplicated name
+        assertEquals(1, duplicatedGroupAuthorities.size());
+
+        pubAuthorityService.deleteAuthority("GROUP_DUPLICATEDGROUP");
+        List<String> duplicatedAuthoritiesAfterDelete = getAuthorityByTypeAndShortName(dublicatedAuthorityType, dublicatedAuthorityShortName);
+        assertEquals(0, duplicatedAuthoritiesAfterDelete.size());
+    }
+
+    /**
+     * Returns the list of authorities according the authority type and authority short name
+     * @param type authority type
+     * @param shortName authority short name
+     * @return List of String authorities
+     */
+    private List<String> getAuthorityByTypeAndShortName(AuthorityType type, String shortName)
+    {
+        return  pubAuthorityService.getAuthorities(type, null, shortName, false, true, new PagingRequest(0, Integer.MAX_VALUE, null)).getPage();
     }
 
     private void checkAuthorityCollectionSize(int expected, List<String> actual, AuthorityType type)