diff --git a/rules/UseSupportsShouldProcess.cs b/rules/UseSupportsShouldProcess.cs
index 16d353587..06b10b32f 100644
--- a/rules/UseSupportsShouldProcess.cs
+++ b/rules/UseSupportsShouldProcess.cs
@@ -65,7 +65,7 @@ private List<DiagnosticRecord> FindViolations()
                 int whatIfIndex, confirmIndex;
                 ParameterAst whatIfParamAst, confirmParamAst;
                 ParamBlockAst paramBlockAst;
-                var parameterAsts = functionDefinitionAst.GetParameterAsts(out paramBlockAst).ToArray();
+                var parameterAsts = functionDefinitionAst.GetParameterAsts(out paramBlockAst)?.ToArray();
                 if (parameterAsts == null)
                 {
                     continue;