And Monroe Freedman famously argued that loyalty and maintenance of confidentiality override duties of candour and honesty to the court (Monroe Freedman Professional Responsibility of the Criminal Defense Lawyer: The Three Hardest Questions (1965) 64 Mich.. (slaw.ca)
Instructing experts The first step is to ask yourself whether you are instructing an expert adviser (someone to help you, not the court) or an expert witness (whose overriding duty is to the court). (newlawjournal.co.uk)
No motive whatsoever can override this duty or free politicians from it. (faith.org.uk)