Advice from a specialist lawyer enjoys legal privilege, i.e. protected confidentiality. This means that your reactions to any situation and the advice given do not have to be disclosed to the aggrieved employee or a tribunal judge. Other HR professionals or consultants don’t have that luxury: we have seen many a defence unravel when those communications are laid bare.
Remember also that the disclosure rules apply equally within your organisation too (when you are not communicating with a lawyer). Any internal emails sent within the management team can also be used at tribunal or obtained via a data subject access request. Be careful what you say and if you want to talk freely, do so to a lawyer. This is especially important now with GDPR.