If the federal securities regulator finds that brokers should adhere to the higher standard, the regulator would be allowed to write rules to that effect, said the senators, who are working on a final regulation bill.
House negotiators still have to sign off on the Senate agreement.
The House and Senate hope to merge their bills this week so they can send a final version of the regulatory overhaul to President Barack Obama to sign into law by early July.
One of the most contentious issues is whether to force brokers who provide financial advice to comply with the same standards as investment advisers.
The House bill contained such a provision. The Senate bill only required a study. Senate negotiators on Tuesday backed the latest proposal from Senator Tim Johnson.
But Christopher Dodd, who helped steer a broad financial regulation bill through the Senate, said senators were going to do more work on the issue.
“I think we’re going to have to do better than the Johnson proposal to get close enough to the House. So we’re working on where that land is,” Dodd told reporters after the sides met to hash out the bill.
Under Johnson’s proposal, the Securities and Exchange Commission’s study would have to conclude that brokers should have fiduciary duties in order to write those rules. The SEC study would also have to detail whether the regulator could adopt such rules for brokers or whether the regulator would need new authority to do so.