One of my colleagues (Steve Kelley) had a very helpful perspective on this. He said that one should always engage with politicians (and other activists) knowing which of three hats you were wearing:
Hat 1. This is my expertise. I am the world expert in this topic. It comes from my research and I am *the* person to talk to about this topic.
Hat 2. This is my field. I know the nuances and questions that one needs to ask. I'm qualified to tell you which science is well-founded and which is bogus.
Hat 3. I'm a citizen. I'm a reasonably smart person who wants to share my opinions on what one should do in this situation.
I've found that talking to politicians being explicit about which hat I'm wearing has been very helpful. (And all three hats can be important. Remember, politicians want to know what their constituents want ... well, good politicians do. This why "call your representative" matters.)
Steve knows from what he is talking about. He was a state senator here in MN and then transitioned to be faculty in our School of Public Affairs. He ran a class once for other faculty in engagement, which is where I got this from.