diff --git a/check.go b/check.go
index 44c0ea2..25ee07b 100644
--- a/check.go
+++ b/check.go
@@ -63,13 +63,13 @@ func Check(root string, dh *DirectoryHierarchy, keywords []string) (*Result, err
 			}
 
 			for _, kv := range kvs {
-				if keywords != nil && !inSlice(kv.Keyword(), keywords) {
-					continue
-				}
 				keywordFunc, ok := KeywordFuncs[kv.Keyword()]
 				if !ok {
 					return nil, fmt.Errorf("Unknown keyword %q for file %q", kv.Keyword(), e.Path())
 				}
+				if keywords != nil && !inSlice(kv.Keyword(), keywords) {
+					continue
+				}
 				curKeyVal, err := keywordFunc(filepath.Join(root, e.Path()), info)
 				if err != nil {
 					return nil, err