CAST - Independence of Test Case & Procedures Developer and Executor

In order to meet independence objectives A6-3 (Level A and B), A6-4 (Level A), and A7-1 (Level A), CAST-26 takes the following position:

"Test Execution: The person responsible for executing the tests should not be the same person who developed the requirements or code being verified by the tests, nor the developer of the test cases and procedures being executed."

I can understand that the test executor should not be the person who wrote the requirements or the code, but cannot really understand why the developer of test cases and procedures cannot execute the test cases. There are occassions when the development of cases and procedures is separated from test execution to ensure that the requirements of gate audits or SOI audits. But I have never come across any software plan or DER insisting on having an independent executor. Is this recommendation an overkill or is there a deeper thought that went into this? I wonder.

Comments

[VIkash]

This is to elimiate the assumption (if any) the developer of Test Cases and Procedures might have made while developing them. If there is an Independent test executor that ensures that Test Execution steps are detailed enough so that they can be executed by any technicians also..

For Eg: How to build a program on the target, How to connect and set up the test environment etc...are the areas where the person working on project may think these things are very common and may not need enough details about it in Test Procedure. However if an independent Test Executor is working on it, he will identify all these gaps..Hope fully I answer your question.

[RMH]

DO-178C resolves all of these issues. It will soon be available.