Will agents have to chose between being listing or selling representative

I have recently heard that new laws might make agents chose whether they want to list a property or sell the property. The law will prohibit them from being the represntative of both parties for one sale. Has anyone else heard anything about this. If it is accurate , that will be a huge blow to an already struggling industry. I constantly hear about problems getting agents to call back and show their properties , when they would be getting the buyer for ther seller. Can you imagine the lack of interest in a listing broker to show their properties , when they can not bring a buyer? I hope this is a rumour .