Graham Lord begins his acknowledgments to “John Mortimer: The Secret Lives of Rumpole’s Creator” (Thomas Dunne, 326 pages, $25.95), in this way:

I must thank Sir John Mortimer himself for giving me two long interviews and encouraging me to write this book before inexplicably he changed his mind and withdrew his cooperation. I should also mention his literary agent, Michael Sissons, whose interference sank the original project but freed me to write the book in half the time it would otherwise have taken and to make it much more interesting and truthful than any authorised biography could.

“Inexplicably”? Surely the biographer has some idea why Mr. Mortimer turned against him. Mr. Mortimer is hardly the first biographical subject to sanction a biography and then pronounce anathema on it. Suddenly Mr. Sissons wanted to see Mr. Lord’s proposal, and Mr. Mortimer put the kibosh on the project.

Perhaps Mr. Lord is puzzled because Mr. Mortimer and his ex-wife, Penelope, spent 20 years turning their stormy marriage into fiction, and then spent another decade giving interviews repeating what they said in their novels. Penelope’s nervous breakdowns and Mr. Mortimer’s infidelities are legendary public knowledge.

Ah, but it is one thing to tell your own story; quite another to let someone else get their mitts on it. Mr. Mortimer has been witty about his failings, which in a biographer’s narrative can seem anything but fun. Indeed, Mr. Lord sees his subject as rather frantic, beaten down by his domineering father (brilliantly portrayed in Mr. Mortimer’s play, “A Voyage Round My Father”), ignored by his mother, and seeking through sexual affairs the love denied him in childhood.

The buoyant Mr. Mortimer, creator of the immortal character Rumpole of the Bailey, is barely visible in Mr. Lord’s sprightly but nevertheless glum recital of his subject’s adventures. But there are some very funny passages that arise out of Mr. Mortimer’s many years as a barrister:

Mortimer loved to tell the story of a young woman victim in an indecent assault case who could not bring herself to say out loud in court what the accused had said to her. ‘Write it down,’ said the judge. She was given a piece of paper, wrote ‘would you care for a screw?’ and the note was passed to the foreman of the jury to read and then from one member of the jury to another until a pretty young jurywoman nudged the twelfth juryman, who seemed to be half asleep, and passed it to him. He read the note, grinned, nodded at her and put it in his pocket. ‘Would you pass that note up to me,’ said the judge. The juryman shook his head. ‘It’s a purely personal matter, my Lord,’ he said.

For almost the first third of Mr. Lord’s biography, he catches Mr. Mortimer in a lie on nearly every other page. The lie-count becomes tedious and begins to look like the unauthorized biographer’s revenge on his subject. Mr. Mortimer’s own daughter called him a “compulsive liar” in the press, so there is no point in objecting to the biographer’s concern with prevarication. But surely Mr. Lord could have dispatched this aspect of Mr. Mortimer with a few choice examples that make the more general point?

It is probably only right to disclose that I have published unauthorized biographies, and that I know Mr. Sissons, who was the soul of cooperation when I worked with him on my biography of Rebecca West. But then, I had her family’s assistance, although I never called myself “authorized.” Indeed, I dislike the term, which smacks of a kind of privilege with which biography ought to have no truck. Mr. Lord’s strategic error, I think, was to call himself authorized. That seems to have riled Mortimer, Sissons & Co. Why could Mr. Lord not have contented himself with simply mentioning his subject’s cooperation? Perhaps even that maneuver would have been enough to brown off Mr. Mortimer.

Mr. Lord also evinces a kind of crudity that possibly dismayed Mr. Mortimer. If the style is the man, then Mr. Lord’s tasteless transitions are surely enough to vex any biographical subject. Mentioning that Mr. Mortimer’s mother did not like “A Voyage Round My Father,” Mr. Lord comments: “so it seemed appropriate that she died of a stroke in Amersham General Hospital the day before it opened.” Or there is this factitious bit: “Barely noticed at Harrow, Mortimer was to spend the rest of his life trying to draw attention to himself.” What happened to Mr. Mortimer at his public school is a lot to load on a lifetime.

As with all biographies, it’s the tidbits that titillate: Hilda, Rumpole’s “she who must be obeyed” was modeled on Margaret Thatcher. The slovenly Rumpole, rumpled and none too clean, is a ringer for Mr. Mortimer himself, known to have mold growing under his fingernails.And Mr. Lord is quite explicit about his subject’s liking for spanking sex.

Mr. Mortimer does not consider himself a brilliant lawyer, but he has won important cases, especially in the area of obscenity law. Indeed, Mr. Lord believes that Mr. Mortimer bears considerable responsibility for the low standards of contemporary permissive society. The key to so much of Mortimer’s life and art is his hostility to authority — authority of any kind. His empathy for criminals, for example, accounts for the colorful felons that Rumpole represents with considerable enthusiasm. Much more felonious in Mr. Mortimer’s canon are the Erskine-Browns, the stuffy, establishment types who clothe themselves in the robes of probity.

Too bad Mr. Lord did not see Mr. Mortimer’s own delinquencies through the prism of his work instead of the other way around, showing how the anarchic life got only partway into the literature. Like many writers, Mr. Mortimer has a gift for story telling that has transformed his life so that it is not always easy for him to distinguish between fiction and fact. He said as much when turning his father into a character. So Mr. Mortimer has done for himself, and it seems somehow mean-spirited of Mr. Lord not to appreciate more fully the playfulness of his subject’s creation.

crollyson@nysun.com