Disabling Stack Trace

Hi,
I have a ASMX web service in my project and provision has been made in all method to not return the stack trace of any error thrown, as it was required by the security team.
While testing when they pass incorrect JSON parameters, they get an error Invalid JSON Parameters along with a Stack Trace of that error. Like below:-
Error{"Message":"Invalid JSON primitive: descpop.","StackTrace":"   at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializePrimitiveObject()\r\n   at System.Web.Script.Serialization.JavaScriptObjectDeserializer.DeserializeInternal(Int32 depth)\r\n   at System.Web.Script.Serialization.JavaScriptObjectDeserializer.BasicDeserialize(String input, Int32 depthLimit, JavaScriptSerializer serializer)\r\n   at System.Web.Script.Serialization.JavaScriptSerializer.Deserialize(JavaScriptSerializer serializer, String input, Type type, Int32 dep ...