Should the Securities and Exchange Commission hold investment advisors and broker/dealers to the same standard of fiduciary duty? While most industry groups are opposed to the idea, at least one has now weighed in with a resounding endorsement.

In a letter to the SEC, the Financial Planning Coalition said it would oppose any efforts to weaken the fiduciary standard. It urged the regulatory body to adopt a uniform fiduciary duty standard that would apply to both broker/dealers and investment advisers when providing personalized investment advice to retail customers.

"This standard should be based upon the core principle that … a financial adviser (however registered) always must act in the best interests of those customers," the letter said. "The SEC should adopt this uniform fiduciary standard immediately."