diff -r 2d71d0f954fb Include/errcode.h
--- a/Include/errcode.h	Sat Jan 17 17:33:49 2015 -0800
+++ b/Include/errcode.h	Sun Jan 18 00:33:55 2015 -0500
@@ -30,7 +30,8 @@
 #define E_EOLS		24	/* EOL in single-quoted string */
 #define E_LINECONT	25	/* Unexpected characters after a line continuation */
 #define E_IDENTIFIER    26      /* Invalid characters in identifier */
-#define E_BADSINGLE	27	/* Ill-formed single statement input */
+#define E_IDENTIFIER_START    27      /* Identifier starts with invalid character */
+#define E_BADSINGLE	28	/* Ill-formed single statement input */
 
 #ifdef __cplusplus
 }
diff -r 2d71d0f954fb Include/unicodeobject.h
--- a/Include/unicodeobject.h	Sat Jan 17 17:33:49 2015 -0800
+++ b/Include/unicodeobject.h	Sun Jan 18 00:33:55 2015 -0500
@@ -591,6 +591,13 @@
 
 #define Py_UNICODE_REPLACEMENT_CHARACTER ((Py_UCS4) 0xFFFD)
 
+#define PyUnicode_IDENTIFIER_INVALID_START 0
+#define PyUnicode_IDENTIFIER_INVALID_IS_EMPTY 1
+#define PyUnicode_IDENTIFIER_INVALID_CONTINUE 2
+#define PyUnicode_IDENTIFIER_INVALID_CHARACTER 3
+#define PyUnicode_IDENTIFIER_NOT_READY 4
+#define PyUnicode_IDENTIFIER_VALID 5
+
 /* === Public API ========================================================= */
 
 /* --- Plain Py_UNICODE --------------------------------------------------- */
@@ -2069,6 +2076,7 @@
 /* Checks whether argument is a valid identifier. */
 
 PyAPI_FUNC(int) PyUnicode_IsIdentifier(PyObject *s);
+PyAPI_FUNC(int) PyUnicode_ValidateIdentifier(PyObject *s);
 
 #ifndef Py_LIMITED_API
 /* Externally visible for str.strip(unicode) */
diff -r 2d71d0f954fb Lib/test/badsyntax_3131_start.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Lib/test/badsyntax_3131_start.py	Sun Jan 18 00:33:55 2015 -0500
@@ -0,0 +1,3 @@
+# -*- coding: utf-8 -*-
+# While è is valid ̀e is not
+̀e = 2
diff -r 2d71d0f954fb Lib/test/test_pep3131.py
--- a/Lib/test/test_pep3131.py	Sat Jan 17 17:33:49 2015 -0800
+++ b/Lib/test/test_pep3131.py	Sun Jan 18 00:33:55 2015 -0500
@@ -27,6 +27,13 @@
               "invalid character in identifier (badsyntax_3131.py, line 2)")
         else:
             self.fail("expected exception didn't occur")
+        try:
+            from test import badsyntax_3131_start
+        except SyntaxError as s:
+            self.assertEqual(str(s),
+              "invalid start character in identifier (badsyntax_3131_start.py, line 3)")
+        else:
+            self.fail("expected exception didn't occur")
 
 def test_main():
     support.run_unittest(PEP3131Test)
diff -r 2d71d0f954fb Objects/unicodeobject.c
--- a/Objects/unicodeobject.c	Sat Jan 17 17:33:49 2015 -0800
+++ b/Objects/unicodeobject.c	Sun Jan 18 00:33:55 2015 -0500
@@ -11796,6 +11796,16 @@
 int
 PyUnicode_IsIdentifier(PyObject *self)
 {
+    if(PyUnicode_ValidateIdentifier(self) == PyUnicode_IDENTIFIER_VALID) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
+int
+PyUnicode_ValidateIdentifier(PyObject *self)
+{
     int kind;
     void *data;
     Py_ssize_t i;
@@ -11803,12 +11813,12 @@
 
     if (PyUnicode_READY(self) == -1) {
         Py_FatalError("identifier not ready");
-        return 0;
+        return PyUnicode_IDENTIFIER_NOT_READY;
     }
 
     /* Special case for empty strings */
     if (PyUnicode_GET_LENGTH(self) == 0)
-        return 0;
+        return PyUnicode_IDENTIFIER_INVALID_IS_EMPTY;
     kind = PyUnicode_KIND(self);
     data = PyUnicode_DATA(self);
 
@@ -11822,12 +11832,15 @@
        as starting an identifier.  */
     first = PyUnicode_READ(kind, data, 0);
     if (!_PyUnicode_IsXidStart(first) && first != 0x5F /* LOW LINE */)
-        return 0;
-
+        if(!_PyUnicode_IsXidContinue(first)) {
+            return PyUnicode_IDENTIFIER_INVALID_CHARACTER;
+        } else {
+            return PyUnicode_IDENTIFIER_INVALID_START;
+        }
     for (i = 1; i < PyUnicode_GET_LENGTH(self); i++)
         if (!_PyUnicode_IsXidContinue(PyUnicode_READ(kind, data, i)))
-            return 0;
-    return 1;
+            return PyUnicode_IDENTIFIER_INVALID_CONTINUE;
+    return PyUnicode_IDENTIFIER_VALID;
 }
 
 PyDoc_STRVAR(isidentifier__doc__,
diff -r 2d71d0f954fb Parser/tokenizer.c
--- a/Parser/tokenizer.c	Sat Jan 17 17:33:49 2015 -0800
+++ b/Parser/tokenizer.c	Sun Jan 18 00:33:55 2015 -0500
@@ -1317,11 +1317,16 @@
         }
         return 0;
     }
-    result = PyUnicode_IsIdentifier(s);
+    result = PyUnicode_ValidateIdentifier(s);
     Py_DECREF(s);
-    if (result == 0)
+    if (result == PyUnicode_IDENTIFIER_INVALID_START) {
+        tok->done = E_IDENTIFIER_START;
+        return 0;
+    } else if(result != PyUnicode_IDENTIFIER_VALID) {
         tok->done = E_IDENTIFIER;
-    return result;
+        return 0;
+    }
+    return 1;
 }
 #endif
 
@@ -1477,7 +1482,6 @@
         tok_backup(tok, c);
         if (nonascii &&
             !verify_identifier(tok)) {
-            tok->done = E_IDENTIFIER;
             return ERRORTOKEN;
         }
         *p_start = tok->start;
diff -r 2d71d0f954fb Python/pythonrun.c
--- a/Python/pythonrun.c	Sat Jan 17 17:33:49 2015 -0800
+++ b/Python/pythonrun.c	Sun Jan 18 00:33:55 2015 -0500
@@ -1325,7 +1325,9 @@
     case E_LINECONT:
         msg = "unexpected character after line continuation character";
         break;
-
+    case E_IDENTIFIER_START:
+        msg = "invalid start character in identifier";
+        break;
     case E_IDENTIFIER:
         msg = "invalid character in identifier";
         break;