Constitutional Reform and Governance Bill

I would like to ask the Minister why it is deemed necessary to specify, in clause 5(2), that""the Minister may publish separate codes of conduct covering civil servants who serve the Scottish Executive or the Welsh Assembly Government."" Given that codes of conduct are about matters of principle, why should those principles be different for civil servants who serve the Scottish Executive or the Welsh Assembly? I appreciate that the policies and procedures are different, as indeed they should be in a devolved situation, but why should the codes of conduct be different?