diff --git a/examples/pipelines/logistic_stats/pipeline.py b/examples/pipelines/logistic_stats/pipeline.py
index b882161..0faf346 100644
--- a/examples/pipelines/logistic_stats/pipeline.py
+++ b/examples/pipelines/logistic_stats/pipeline.py
@@ -113,9 +113,9 @@ def model(dhis2_data: dict[str, typing.Any], gadm_data, worldpop_data):
     population_df = pd.Series(data=[stat["sum"] for stat in stats], index=administrative_areas.index)
     population_df = pd.DataFrame({"District": administrative_areas["NAME_2"], "Population": population_df})
     corrected_population_df = population_df.copy()
-    corrected_population_df.loc[
-        corrected_population_df["District"].str.startswith("Western"), "District"
-    ] = "Western Area"
+    corrected_population_df.loc[corrected_population_df["District"].str.startswith("Western"), "District"] = (
+        "Western Area"
+    )
 
     corrected_population_df = corrected_population_df.groupby("District").sum()
 
diff --git a/openhexa/sdk/pipelines/parameter.py b/openhexa/sdk/pipelines/parameter.py
index 203e217..a913b37 100644
--- a/openhexa/sdk/pipelines/parameter.py
+++ b/openhexa/sdk/pipelines/parameter.py
@@ -487,7 +487,12 @@ def _validate_default(self, default: typing.Any, multiple: bool):
         except ParameterValueError:
             raise InvalidParameterError(f"The default value for {self.code} is not valid.")
 
-        if self.choices is not None and default not in self.choices:
+        if self.choices is not None:
+            if isinstance(default, list):
+                if not all(d in self.choices for d in default):
+                    raise InvalidParameterError(
+                        f"The default list of values for {self.code} is not included in the provided choices."
+                    )
             raise InvalidParameterError(f"The default value for {self.code} is not included in the provided choices.")
 
     def parameter_spec(self) -> dict[str, typing.Any]:
diff --git a/openhexa/sdk/pipelines/runtime.py b/openhexa/sdk/pipelines/runtime.py
index 9b7d54e..ee70a3c 100644
--- a/openhexa/sdk/pipelines/runtime.py
+++ b/openhexa/sdk/pipelines/runtime.py
@@ -36,8 +36,12 @@ class PipelineParameterSpecs:
 
     def __post_init__(self):
         """Validate the parameter and set default values."""
-        if self.default and self.choices and self.default not in self.choices:
-            raise ValueError(f"Default value '{self.default}' not in choices {self.choices}")
+        if self.default and self.choices:
+            if isinstance(self.default, list):
+                if not all(d in self.choices for d in self.default):
+                    raise ValueError(f"Default list of values {self.default} not in choices {self.choices}")
+            elif self.default not in self.choices:
+                raise ValueError(f"Default value '{self.default}' not in choices {self.choices}")
         validate_pipeline_parameter_code(self.code)
         if self.required is None:
             self.required = True
@@ -180,7 +184,7 @@ def get_pipeline_metadata(pipeline_path: Path) -> PipelineSpecs:
                         Argument("name", [ast.Constant]),
                         Argument("choices", [ast.List]),
                         Argument("help", [ast.Constant]),
-                        Argument("default", [ast.Constant]),
+                        Argument("default", [ast.Constant, ast.List]),
                         Argument("required", [ast.Constant]),
                         Argument("multiple", [ast.Constant]),
                     ),
diff --git a/openhexa/utils/stringcase.py b/openhexa/utils/stringcase.py
index e79a274..f2acdbe 100644
--- a/openhexa/utils/stringcase.py
+++ b/openhexa/utils/stringcase.py
@@ -2,6 +2,7 @@
 
 Coming from https://github.com/okunishinishi/python-stringcase
 """
+
 import re