diff --git a/code/models/fieldtypes/JSONText.php b/code/models/fieldtypes/JSONText.php
index 9aa753f..5adcc2d 100755
--- a/code/models/fieldtypes/JSONText.php
+++ b/code/models/fieldtypes/JSONText.php
@@ -553,7 +553,7 @@ public function isValidOperator($operator)
      */
     public function isValidExpression($expression)
     {
-        return (bool) preg_match("#^\\$\.#", $expression);
+        return (bool) preg_match("#^(\\*|\[\d:\d:\d\]|\\$\.+[^\d]+)#", $expression);
     }
     
     /**
diff --git a/tests/JSONTextTest.php b/tests/JSONTextTest.php
index 5dc2a82..72bba15 100755
--- a/tests/JSONTextTest.php
+++ b/tests/JSONTextTest.php
@@ -12,15 +12,21 @@ class JSONTextTest extends SapphireTest
 {
     /**
      * @todo There are a ton more permutations of a JSONPath regex
-     * See the walk() method in JSONStore
+     * See the trace() method in JSONPath for more examples to work from
      */
     public function testIsValidExpression()
     {
         $field = JSONText::create('MyJSON');
         
         $this->assertTrue($field->isValidExpression('$..'));
+        $this->assertTrue($field->isValidExpression('*'));
         $this->assertTrue($field->isValidExpression('$.[2]'));
         $this->assertTrue($field->isValidExpression('$.cars.american[*]'));
+        $this->assertTrue($field->isValidExpression('[0:1:1]'));
+        $this->assertFalse($field->isValidExpression('[0:1:]'));
+        $this->assertFalse($field->isValidExpression('[0:1:1'));
+        $this->assertFalse($field->isValidExpression(''));
+        $this->assertFalse($field->isValidExpression('$.1.cars.american[*]'));
         $this->assertFalse($field->isValidExpression('$'));
         $this->assertFalse($field->isValidExpression('$[2]'));
     }