Daniel Kanstroom is a professor of law at Boston College and co-director of the university’s Center for Human Rights and International Justice.

O f all the associations one might have with the name John Lennon, “ deportable alien ” would not be likely to top many lists. And yet, according to Leon Wildes, a well-known and highly respected immigration lawyer for more than half a century, the former Beatle’s most enduring legacy may not be musical, artistic or cultural, but — strangely — legal.

More than 40 years after litigating what was undoubtedly the deportation case of his lifetime, Wildes has written an engaging book, “John Lennon vs. the USA,” that recounts a remarkable (and remarkably complex) legal story. The tale has been told before (in many articles written by Wildes and in a documentary, “The U.S. vs. John Lennon,” released in 2006). However, the book adds important details and a rather bold claim. It suggests that the roots of President Obama’s highly controversial assertion of broad discretionary power to shield millions from deportation lie in a most strange place: the Nixon administration’s rather sordid but ultimately unsuccessful attempt to deport Lennon and Yoko Ono in the early 1970s. (Both got green cards and were allowed to live permanently in the United States. Lennon was murdered in New York in 1980 before he could apply for citizenship.)

Wildes argues that “John’s legacy is a broad attempt to reform the immigration process in a humanitarian way.” What he means is that the Lennon case was largely about the controversial idea of government discretion to pursue or not to pursue particular deportation cases. Many millions of people in this country are potentially subject to deportation. But they cannot all be removed without a massive effort that would be politically, economically and morally unacceptable. The government must establish priorities. But when do such priorities become equivalent to lawmaking, and thus reserved to the legislative branch of government? This, essentially, was the issue on which the Supreme Court recently split, 4 to 4, regarding Obama’s executive action to grant “deferred action” to certain undocumented parents of U.S. citizens and lawful permanent residents, and to some who came to the United States as children.

"John Lennon vs. The U.S.A.: The Inside Story of the Most Bitterly Contested and Influential Deportation Case in United States History" by Leon Wildes and Michael Wildes (American Bar Association )

Though it took Wildes years to prove it in the Lennon case, there was a secret system of discretion in play in those days. That sort of discretion strongly contradicts basic ideas of justice and fairness. As one court put it in regard to Lennon’s case, “The courts will not condone selective deportation based upon secret political grounds.” But once the system of discretion was brought to light, it grew and became more transparent and generous. In that sense, Wildes suggests, Lennon’s legacy was to open this process up and to allow it to flourish.

The full history of discretion in immigration enforcement is considerably more complex than Wildes suggests in his rather informal, accessible but detailed narrative, as are the roots of Obama’s recent actions. Still, the Lennon saga reveals much of the eye-crossing intricacy, harshness and dysfunction of our immigration system. And for those of us of sufficient age to remember John and Yoko, the book is also, if not a complete magical mystery tour of the 1970s Kulturkampf, still a precious ticket to ride back in time.

There is much to like in this book. Wildes captures readers’ attention from his first encounter with John and Yoko in 1972. Though already a successful lawyer, he seems to have been remarkably naive about popular culture, claiming to have been so insulated from it at the time that he did not even know who Lennon was! The book contains charmingly intimate stories of John and Yoko, who, among other stunts, sent a bouquet of flowers to the New York director of the Immigration and Naturalization Service and declared themselves to be ambassadors from the made-up, free state of Nutopia, which “granted them diplomatic immunity from any further deportation proceedings.”

It also walks us through a fascinating recitation of legal complexities, litigation strategies, courtroom tactics and celebrity witnesses ranging from John V. Lindsay to Jack Lemmon, Fred Astaire and a young Geraldo Rivera. It will be especially interesting for lawyers and for those who are curious about how immigration law actually works.

The essence of Wildes’s story is simple. Its main bete noir is President Richard Nixon, along with a variety of government underlings who, at best, seem to have lacked the character and fortitude to resist pressure from above. Nixon, we are told, hated and feared Lennon as an inspiration to — and potential organizer of — the newly authorized 18-to-21-year-old vote. The president apparently discovered that Lennon, who was then temporarily living in New York with Ono, was potentially subject to deportation (he had pleaded guilty in 1968 to possession of cannabis resin in Britain). The law was not so simple on this score, however. It referred to marijuana, not cannabis resin. Wildes recounts being ignorant of the difference between cannabis resin (also known as hashish) and marijuana. Lennon explains the difference to him from one perspective: “Hash is much better than marijuana!”

But it turns out that arcane technical details, then as now, can have dramatic effects in deportation cases. Indeed, a federal court ultimately concluded that Lennon was not, technically, subject to exclusion for this British conviction. Moreover, Lennon had been granted a waiver, a sort of forgiveness. How could he now be deported for an offense that the U.S. government had previously forgiven? How indeed, when part of the story was also John and Yoko’s poignant search for her daughter, who they claimed had been illegally taken from her by the child’s father?

Nixon and his cohort were apparently untroubled by legal niceties and such humane considerations. Along with the FBI, according to Wildes, they engaged in the sort of dirty tricks that, to this day, are referred to as Nixonian. Wildes recounts that Nixon, who had earlier ordered a politically motivated, vindictive raid against the Los Angeles Times to search for “illegal aliens,” was well aware of the power of immigration law to support partisan politics. Wildes, making his case, reprints various government documents he obtained through vigorous use of the Freedom of Information Act. Indeed, much of the book is a paean to the enduring importance and power of FOIA. A particularly chilling example is a 1972 memo from the arch-segregationist Strom Thurmond, then a member of the internal security subcommittee of the Senate Judiciary Committee, urging Attorney General John Mitchell to take “appropriate action” against Lennon to avoid “many headaches.” Equally revealing is a 1972 memorandum to Nixon’s assistant H.R. Haldeman specifically linking Lennon’s alleged political activities to the deportation case against him.

Of course, this sort of thing was not new then, though it was not widely known. Wildes does not mention it, but J. Edgar Hoover, who shuffles on and off stage throughout the book, was involved in deporting radicals early in his career with the Justice Department’s general intelligence division. He deported Emma Goldman in 1919 and other anarchists and leftist dissidents during an earlier ideological deportation episode in New York. The discretionary targeting of political opponents, in short, had a long history before Lennon encountered it. But it was always a sort of dirty little secret that challenged our fidelity to the best principles of the rule of law.

In that sense, much of the significance of this book lies in its revelation of the strange and complex history of immigration law in our nation of immigrants. Laws of exclusion and deportation have been especially hard to reconcile with legal principles of due process and equal protection. Though current debates have focused mostly on recent deportations of millions of undocumented workers and their families by the George W. Bush and Obama administrations, our immigration laws have long embodied all sorts of prejudices that we have proudly rejected in other legal arenas. And yet, the attempted exclusion and deportation of political opponents, petty criminals, and those seen as immoral or dangerous has often achieved popular support and has tempted governments from the very founding of the republic. The debates have been fierce. The 1798 Alien and Sedition Acts, the earliest federal effort to empower the president to deport undesirables (mostly Irish and French opponents of John Adams’s Federalists), were decisively criticized by Thomas Jefferson, James Madison and others as an unjust assault on “the friendless alien” and a violation of deep principles of justice and fairness. As later became true of Lennon’s case, much of the critique was directed at the discretionary nature of these laws, which empowered the president to summarily deport “all such aliens as he shall judge dangerous to the peace and safety of the United States, or shall have reasonable grounds to suspect are concerned in any treasonable or secret machinations against the government thereof.”

Since their reinvigoration in the late 19th century, with a set of racist laws aimed specifically at Chinese laborers, exclusion and deportation have become massive, complicated and harsh legal systems. Many millions have been deported, some after court hearings but many summarily. Some have seen regard for family connections or personal hardships, but many have been given no such consideration. Through it all, a deep question has remained: What is the right relationship between executive discretionary power to exclude and deport and the basic rights of aliens (a peculiarly offensive word for noncitizens that nevertheless remains a technical term of art in the immigration statutes)? And what is the right relationship between the power of Congress to enact strict deportation laws and the power of the executive branch to ameliorate harshness with so-called prosecutorial discretion?

These are questions that will undoubtedly recur and about which the evocatively titled “John Lennon vs. the USA” offers important insights and engaging historical lessons.