This piece was originally published on Just Security, an online forum for analysis of U.S. national security law and policy.

On Sunday, President Donald Trump launched a new phase in his attack on the Department of Justice and Robert Mueller’s investigation. He is now going beyond rhetoric: He is apparently preparing to announce, as an “official act,” a directive to DOJ to inquire into alleged irregularities in the Russia investigation. His stated reason is the belief that the department used an informant to infiltrate his campaign in 2016 in the early stages of what has now become the Mueller inquiry into Trump campaign–Russia collusion. As the president goes down this path, he has also collaborated with House Intelligence Committee Chairman Devin Nunes and allied media outlets to disregard strong objections from the FBI and the intelligence community to achieve the “outing” of an intelligence source whom Trump suspects of this infiltration.

We have arrived at the point where Trump is testing the theory that he has the unfettered constitutional power to initiate, direct, or conclude any criminal investigation for any reason whatever—including self-protection. His lawyers have floated this theory from time to time, but, after all, they are his lawyers. A more prominent, presumably independent judgment has come via the airwaves and in print from Alan Dershowitz. The Harvard Law professor emeritus has been everywhere with the message that the charges against Trump are “trumped up” and that the president has the authority to control the course—and, as he wishes, terminate—the investigation against him. The president has tweeted his approval and welcomed Dershowitz to the White House.

Dershowitz has gone so far as to write a book to elaborate his views, Trumped Up: How Criminalization of Political Differences Endangers Democracy. When Dershowitz appears as a cable show guest, the hosts often introduce him with a reference to the book. At a New York City event at which Dershowitz appeared along with others in a debate about the Russia matter, the book was handed out, gratis, to the guests. Dershowitz is promoting the book as an explication of his position—certainly a more extensive presentation of his argument than five-to-seven-minute interviews could ever provide. Now, more than ever, the argument requires close examination, and it seems that in evaluating Dershowitz’s case, his written brief on the subject should count for as much as, if not more, than what he has said on TV.

The first and most puzzling feature of the book is that it is only in minor part dedicated to the issue suggested by the title. Numerous sections don’t address the topic at all. Many deal with Middle East policy. A few discuss the challenges to the Trump travel ban, which might well engage Dershowitz’s civil libertarian concerns, but do not directly relate to the Mueller investigation or the “criminalization of politics.” He discusses, among other topics, the Clinton-Sanders primary battle; his objection to the candidacy of Keith Ellison for chairman of the Democratic National Committee; his views on the appointment of Steve Bannon to the White House staff; his reflections on a visit to Cuba; and the importance of shoring up the center in American politics generally and in the Democratic Party in particular. In fact, of the 193 pages in the book, 54—only 28 percent—deal in any way with the Trump legal position in the Russian investigation.

How to account for this continuous diversion from the main point? It could be mostly a case of filling out the book, which is short. It does seem, however, that if Dershowitz is to declare that the legal claims against the president are “trumped up,” a symptom of the criminalization of American politics, his book by that title might be expected to present some sustained and coherent argument—something more than disparate opinion pieces. This is not to be found in this writing.

It comes as a surprise that on the main point—that the Russian allegations and Mueller inquiry are symptoms of the criminalization of American politics—Dershowitz advances bold propositions in defense of the president, and against the Mueller inquiry, then suddenly retreats. It is almost as if he begins by giving a written version of his TV appearances but, when putting his fingers to the keyboard, the law professor in Dershowitz begins to hedge. He is noted for his table-banging mode of argument, and yet on these issues he pauses to acknowledge, almost as an aside, that maybe nothing is quite as simple as he makes it seem. He tends to try to overcome these hesitations, and still drive home his point about the “criminalization of political differences” by drawing dubious distinctions and relying on questionable authority.

Take, for example, Dershowitz’s position that a president cannot be charged with obstruction for “properly exercising his constitutional authority,” as in firing a subordinate. He disputes that a president’s motive is ever subject to judicial inquiry. In other words, the facts, insofar as they bear on motive, don’t matter: Presidents can fire law enforcement officials and direct investigations. “[M]otive alone should never constitute a crime” where the president is taking action within “his statutory and constitutional authority,” Dershowitz writes, and so “no one should doubt” that the president could fire the director of the FBI “for any reason or no reason.” So, if there is clear evidence that the president was motivated exclusively by the aim of protecting himself from prosecution, it is a reason like any other and therefore immune from inquiry in the legal process. The president can do what he did “for any reason.”

But it then appears that Dershowitz equivocates. He seems to concede that James Comey’s account of the president’s request of him in the Michael Flynn matter that he “let this go” raises a “complex constitutional issue.” He writes that the “conclusion might well depend on what precisely the president asked the FBI director to do.” By the time Dershowitz arrives on the last and final page of his discussion, he decides that “on balance, the obstruction case against President Trump is not strong, as a matter of law.”

So all of a sudden, what Dershowitz seems to have presented as an absolute principle of constitutional law—the president’s authority to fire law enforcement officials for any reason, even for a corrupt one—hinges on the facts and only favors Trump’s position “on balance.” At one point, Dershowitz dissects Comey’s congressional testimony to show that what Trump suggested that the FBI director do—or not do—with the Flynn case cannot be taken to be a clear case of obstruction. Dershowitz states that Trump “certainly acted within his constitutional authority if he merely requested or ‘hoped’ that Comey stand down.” But the reader must wonder: Does the president enjoy complete immunity from judicial inquiry, or does liability turn on the facts? And if the latter, and in the absence of the full facts being pursued by the special counsel, on what basis does Dershowitz claim with such confidence that the allegations against the president are “trumped up” and that the president “had the constitutional authority to order Comey to end the investigation of Flynn.”

Later, Dershowitz continues with this mode of equivocation when he states that “it is probably not an indictable offense for the president to have fired the Director of the FBI and/or asked him to ‘let it go’ with regard to his national security adviser” (emphasis is mine). This probably would startle anyone who followed his argument to that point (not to mention those who have heard him put forward these arguments in his public appearances).

Then there is the matter of the constitutional history on which Dershowitz arrives in concluding that “on balance” the president did not commit obstruction of justice in the Flynn matter. Dershowitz insists on the significance of “historical context”—that other presidents have directed prosecutions, as Thomas Jefferson did in insisting that his attorney general prosecute Aaron Burr for treason. He cites also, vaguely, the fact that “President John Kennedy and Lyndon Johnson interacted with FBI Director J. Edgar Hoover.”

In neither case does Dershowitz suggest that these presidents engaged in these activities to defend themselves from personal legal liability. It is not even clear what Dershowitz has in mind when referring to Kennedy and Johnson’s “interactions” with Hoover. Nothing in the prerogative of presidents to “interact” with law enforcement bears on the question of whether they can impede or end an investigation directed against them.

The Dershowitz treatment of the pardon power is similarly short on sustained argument, internally inconsistent, and long on the questionable use of “historical context.” Dershowitz has stated elsewhere about pardons what he writes about the question of obstruction: “The granting of [a] pardon would not be a crime. I do not believe that engaging in a constitutionally authorized act can ever be the basis of a criminal charge.” In his book, he affirms his belief that this power “would seem absolute and not subject to constraints either from Congress, the courts or legal ethics.”

But once again, he equivocates: He admits that he is not certain that a president can pardon himself. And this is the reason he gives:

[T]he common law and long accepted rules of legal ethics preclude anyone from being a judge in his or her own case. A president pardoning herself would be engaging in a massive conflict of interest that the public would never accept, just as it didn’t accept Nixon’s firing of the special prosecutor Archibald Cox.

Here, while Dershowitz is also speaking to the ethics or public-political acceptability of a self-pardon, he is clearly conceding a potential legal limitation, or least a legal question, since he describes the issue as a puzzle to “law professors and legal scholars since the Watergate scandal involving Richard Nixon.” And he refuses to commit on this fundamental “question of whether a president may pardon him or herself.” His bottom-line conclusion: “[N]obody knows for sure.”

But if a president may not be permitted to pardon himself as “judge in his or her own case,” the effect of which would be to obstruct an investigation, why should we think he is able to pardon others—witnesses against him—to the same self-protective effect? If he cannot pardon himself, could he pardon his son-in-law or his daughter? Isn’t that also a “massive conflict of interest”? Does the final answer to these queries once more depend on the facts?

Dershowitz does not say. But he relies on President George H.W. Bush’s Iran-Contra pardons to contend that it is somehow generally understood that, as Trump has said, the pardon power is “complete.” Dershowitz has argued elsewhere that while the Iran-Contra pardons shut down an inquiry that may have affected George H.W. Bush, “it never occurred to anybody” at the time that they may have constituted obstruction. Again, Dershowitz’s resort to “historical context” does not do the work he assigns to it.

First of all, if Dershowitz chooses to rely heavily on “historical context,” then he should also acknowledge its complexities and limitations. G.H.W. Bush pardoned former Secretary of Defense Caspar Weinberger and others on his way out of office, in December 1992, and no one in the incoming Clinton administration had an appetite for or interest in a fight over the pardons when they were setting up a new government and preparing for their first 100 days. Had Bush won re-election, it is entirely possible that it would have “occurred” to someone—say, to Democrats in the opposition—that there was an argument for obstruction. What’s more, Dershowitz is arguing not only that nobody made this allegation at the time of the pardons but that it would never have occurred to anyone to make it—which is seriously overarguing his point and certainly incorrect.

More important, the Iran-Contra matter was not an investigation in the first instance into the private wrongdoing of a president or an organization—such as the Trump campaign—that he controlled. As far as many Republicans were concerned, what the Democrats characterized as a scandal was, in fact, an institutional conflict between Congress and the executive over the conduct of foreign affairs. So, as Jeffrey Crouch has written, they viewed the pardons “as a legitimate end result of a political struggle.” To the extent that President Bush’s personal legal position was implicated, if at all, that issue arose out of the conduct of the investigation and the question of whether his account of his role as vice president in Iran-Contra squared with evidence that might have surfaced if the inquiry had continued. It was not alleged that Bush stood to gain personally from whatever role he had in lending his support or approval to the Iran-Contra scheme.

Right or wrong, this view is clearly distinguishable from the facts surrounding the Russia investigation. Republicans who support Trump’s position in the matter deny that there was Trump campaign collusion with the Russians in the 2016 election: They never suggest that, had it occurred, it would have been a legitimate strategic choice that Trump and his campaign might have made to win the election. In issuing the pardon in the Iran-Contra matter, President Bush said of the officials in question that “they did not profit or seek to profit from their conduct” but were caught up in a “profoundly troubling development in the political and legal climate of our country: the criminalization of policy differences.” By contrast, there is no chance that, if any Trump campaign officials are indicted for coordinating campaign activities with the Russian government, and the president then pardons them, anyone will think to justify this action by appealing to the campaign operatives’ public spiritedness and defending prosecution of an electoral alliance with the Kremlin as a “criminalization of policy differences.” Dershowitz’s failure to see or acknowledge this distinction is a telling example of what is misguided about the thesis he sketches out, with so broad and undiscriminating a brush, in these pages of his book.

Dershowitz’s focus on “criminalization” drives him to say in this book, as he has repeatedly stated on air, that he sees no legal basis for the charge of collusion. He grants it could be the basis for impeachment but not for legal prosecution: “Even if there was such direct links [or coordination], that would not constitute a crime under current federal law.” Nowhere in the book is there any mention of the campaign finance laws, which prohibit foreign nationals from spending funds to influence U.S. elections and—of crucial importance—forbid U.S. national solicitation of or support for this spending. Dershowitz is free to argue, if he chooses, that he would not have the law apply in this instance. It is not a defensible choice to ignore the law altogether.

Without doubt, Dershowitz is a committed civil libertarian, and there is also no question that he believes that his aim is only to “call ‘em as I see ‘em from a civil liberties perspective without regard to the political implications of my positions.” While writing in defense of Trump’s legal position on the Russia-related matters, he is also critical of the president on issues such as his threat to change the libel laws to ease access to the courts to sue the press, as well as the president’s support for a criminal prohibition on flag burning.

But on the two major issues of the day—addressing the Russia allegations and outlining the president’s constitutional defense against the Mueller inquiry—Dershowitz seriously understates the significance of the former and presents a confused and misleading picture of the latter. His constitutional arguments fall short of adequately supporting authority and suffer from deep internal inconsistencies, and he appends his assertions with surprising qualifications that significantly undermine the overall power of his publicly stated positions. These weaknesses are far more clear in his writing than in the oral presentation with which cable television viewers have become familiar.

To be fair, Dershowitz may be the most visible legal commentator to make sweeping public pronouncements, but he is not the only one, and the same rigor should be expected of those arguing the other side of the case. All engaged scholars have to struggle with political and moral convictions that, consciously or unconsciously, can sway their legal judgments. This is an even greater challenge in addressing the issues raised by the actions, words, and tweets of Donald Trump, whose “unprecedented actions,” Dershowitz writes, “raise unprecedented legal, constitutional, civil liberty, and ethical issues.”

Dershowitz has so far not done justice to those issues. Having seized the public stage with his customary panache, he should have to face hard questions about the quality of the case he is putting forward. His book does not supply answers: It only raises more questions about his overall project.

On one level, that project is unexceptionable, even commendable: His chief complaint about intense political conflicts risking the criminalization of differences, which leads him to warn about independent or special counsel inquiries, is fully consistent with a civil liberties commitment. He told Evan Mandery of Politico that he wished to be a “public educator” on these issues. But Dershowitz has made the choice to go much further and to make inadequately supported and reasoned claims about “trumped up” allegations against the president and his campaign, and about the failure of Trump’s critics to appreciate his constitutional powers and immunities. Ironically, and unfortunately, the charge of “trumped up” is more true of the president’s and Dershowitz’s attacks on the Mueller inquiry and of their constitutional defense of unfettered presidential control of federal law enforcement. And, as we are seeing now, these claims are not without consequence.

More from Just Security:

Getting to the Bottom of the Trump Tower Meeting

Dispelling the NYT’s “The Daily” Podcast’s Misconceptions About Mueller’s Options