diff --git a/spacy/pipeline/tagger.pyx b/spacy/pipeline/tagger.pyx
index ae59d0983..243657517 100644
--- a/spacy/pipeline/tagger.pyx
+++ b/spacy/pipeline/tagger.pyx
@@ -258,8 +258,8 @@ class Tagger(TrainablePipe):
         DOCS: https://spacy.io/api/tagger#get_loss
         """
         validate_examples(examples, "Tagger.get_loss")
-        self.cfg["label_smoothing"] = 0.05 if self.cfg["label_smoothing"] else 0.0
-        loss_func = SequenceCategoricalCrossentropy(names=self.labels, normalize=False, neg_prefix=self.cfg["neg_prefix"], label_smoothing=self.cfg["label_smoothing"])
+        label_smoothing = 0.05 if self.cfg["label_smoothing"] else 0.0
+        loss_func = SequenceCategoricalCrossentropy(names=self.labels, normalize=False, neg_prefix=self.cfg["neg_prefix"], label_smoothing=label_smoothing)
         # Convert empty tag "" to missing value None so that both misaligned
         # tokens and tokens with missing annotation have the default missing
         # value None.