diff --git a/lib/galaxy/tools/parameters/basic.py b/lib/galaxy/tools/parameters/basic.py
index b329169eba7..56f9a6d9893 100644
--- a/lib/galaxy/tools/parameters/basic.py
+++ b/lib/galaxy/tools/parameters/basic.py
@@ -2152,6 +2152,8 @@ class DataCollectionToolParameter( BaseDataToolParameter ):
             raise ValueError( "History does not include a dataset collection of the correct type or containing the correct types of datasets" )
         if value in [None, "None"]:
             return None
+        if isinstance( value, dict ) and 'values' in value:
+            value = self.to_python( value, trans.app )
         if isinstance( value, string_types ) and value.find( "," ) > 0:
             value = [ int( value_part ) for value_part in value.split( "," ) ]
         elif isinstance( value, trans.app.model.HistoryDatasetCollectionAssociation ):