You can try that, but the officer does not have to tell you anything. It may be best for him to do so, but there could be reasonable reasons for him not to.
He only needs to be able to justify to a judge that he had reasonable cause. So, it’s up to you, if you don’t think he had reasonable cause to get a lawyer.
You’re still living in 1970. Everyone has dash cam and/or cell phone video. Most cops wear body cams. They know if they eff up its going to go badly for them.
Cops are getting fired all over the country for this stuff and police departments are getting terrible publicity on YouTube. This is a good thing. They are behaving themselves better now.
It pays to know your rights and to be able to articulate them to a police officer so that they understand that you know it and record every interaction. The police cannot just do anything they want to on the side of the road. That’s a fallacy.