Trump loves to play cat and mouse during legal negotiations (including public tweets), while Mueller must maintain a veil of secrecy regarding the negotiations to interview Trump. It is my opinion that the best way to treat a bully (i.e. Trump and/or his lawyer) is to bloody his/their nose with a subpoena, unless he/they fully cooperate with Mueller.
Title: "Trump’s Mueller Interview Endgame"
https://slate.com/news-and-politics/2018/01/trump-is-using-an-interview-offer-as-another-way-to-discredit-the-mueller-probe.htmlExtract: "He is using a negotiation as another way to discredit the investigation.
Federal prosecutors, it is often said, enjoy enormous power advantages over suspects and defendants. There are, however, areas in which the balance of power runs the opposite way. One is the ability to use the media. Criminal suspects and their lawyers have unfettered access to the press, while professional standards and Department of Justice rules severely restrict prosecutors from talking about what they are doing, especially at the investigative stage.
This asymmetry is even greater when the subject of the investigation is President Donald Trump, whose every tweet and utterance draws instant international coverage, and the prosecutor is Robert Mueller, who operates in a political environment that demands irreproachable conduct from him.
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The president, of course, is no ordinary witness. Among other things, he is at serious legal risk in this matter and may effectively be a target of Mueller’s. Department of Justice guidelines, and norms of criminal practice, hold that investigative targets should not be subpoenaed to testify unless doing so is essential to an inquiry.
This rule, together with the president’s extraordinary job responsibilities, gives Trump’s lawyers the ability to force Mueller to deal with their demands.
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Mueller is left in a bind. He cannot agree to an interview under conditions that would make it fruitless. Trump’s apparent version of the interview is a “Did you do it?” scenario that exists only on television. But investigative interviews in white-collar cases involve layered and detailed questions to establish intent. Proclaiming innocence is not the point. On the other hand, Mueller cannot maintain the credibility of his investigation if he does not give the president a chance to tell his side of the story to investigators.
The public will not know the truth about any “negotiations” that took place over interview conditions because they will hear only the president’s version of those events. Perhaps Mueller will decide that he has no choice but to deem the president’s testimony essential and issue a subpoena. The president’s lawyers would then contest the subpoena in court, and the courtroom is at least a playing field where Mueller can and would respond. But if Mueller issues a subpoena, it seems certain that the president would claim this extraordinary action proves that Mueller is simply out to get him. What’s clear is that the next steps in the interview episode could weaken Mueller’s precarious hold on the special counsel position further, as the prospect of Trump ever answering a question in the Russia probe continues to fade."
