CONCORD — A Merrimack Superior Court judge has limited expert testimony by attorney Peter G. Beeson in a contract dispute between Salem real estate developer Berge Nalbandian and attorney Frederick W. Murdock.

The dispute dates back to a series of loans Murdock arranged for Nalbandian during the 1980s while also serving as an officer or partner for the lenders.

Judge Richard B. McNamara ruled Besson can testify to his opinion on whether Murdock could have properly asked Nalbandian to waive the attorney’s conflict of interest.

“Attorney Beeson’s opinion regarding the ‘disinterested lawyer’ standard would assist the jury in rendering a decision about whether or not Murdock breached the rules which govern conflicts of interest,” McNamara wrote in his May 16 decision.

But the judge said other issues to which Beeson planned to testify were the province of the jury.

Murdock sought to block all of Beeson’s testimony.

The case is Frederick W. Murdock, Esq., v. Berge M. Nalbandian, No. 218-2028-CV01062.