Legal Question in Constitutional Law in Indiana

The attorney/client privilege is usually governed by state law, so the answer to your question will vary from one state to the next. The privilege is in the news today due to yesterday's FBI raid of Michael Cohen's office. The privilege between him and President Trump would be governed by New York law, though the laws of other states might be relevant to some communications between the two. If that is what led to your question, you may want to re-post it under New York law and under the category "Legal Ethics & Professional Responsibility."