From the time of my first patent trial in Wilmington, DE, around 1990, the standing order there was no “legal experts.” It was a good rule then, and now, but now the CAFC and the Supreme Court have mixed legal rules with factual issues. Still, in a bench trial, it is close to a professional affront to proffer a lawyer to give the Judge an opinion on the law, even the patent law.
It still is the unwritten rule in Delaware, as indicated in a short Dec. 20th Order in Vanderbilt Univ. v. ICOS Corp., (Civ. 05-506-SLR), where after having “reviewed the case law” the Judge “concluded that testimony to explain (or explain away) such law is neither needed or appropriate.” I suppose that was cause to send that “legal expert” back to gather up his luggage at the DuPont Hotel and Metroliner back to wherever he rode into town from.