A. It's done. Getting it published is a struggle in this brave new world of the book business. We're working on a combination e-book and print deal now. I'll get more information online as soon as publication is set. In this one, a famous immigration lawyer in Los Angeles hires Brinker to investigate two – and maybe many more – murders.

Q. Where did you get the ideas for your books?

A. Tucson is near the U.S. border with Mexico. The local newspaper has stranger-than-fiction stories every day. The problems described in the books – smuggling, border crossings, drugs, exploitation of people – are big news here. It's impossible to write a crime novel set in Southern Arizona without using these very real troubles.

Q. What do the titles mean?

A. "Lovers Crossing" is the name that I gave to a place along the border, near Nogales, where illegal immigrants try to cross. It comes from the dark humor of my Border Patrol characters. There's a double meaning; it also applies to the romantic troubles of several characters. The protagonist, Brinker, and Dolores Gonzales are having problems. And some other couples' entanglements may be connected to the murder at the heart of the story.

"Choke Point" describes conditions on the border at Nogales. The U.S. has concentrated enormous financial and human resources to stop illegal immigration around the border population centers. So areas like Nogales become jammed with legal immigrants and Mexicans looking for factory work in their own country, while the illegal immigrants try to sneak through the worst sections of the desert.

"Our Lady of the North" is the third Brinker, not published yet. The title is the English translation of a nickname, nuestra señora del norte, given to the immigration lawyer by admirers in Latin America.

Q. What is it about the desert that appeals to you as a writer?

A. In some ways, the desert is the last frontier in our country. Robert B. Parker, in his doctoral thesis, suggested that the modern private investigator is like the 18th and 19th century frontiersman, a kind of Natty Bumppo with no western trails left to blaze, so he seeks order in the cities. Brinker seeks it in the desert, the cities and other untamed areas there.

The southwestern desert today is still a wilderness, chaotic and largely ungoverned. People still brave it to find a better life. These can be hopeful Americans who leave communities in the east or midwest to come here in conventional ways, or people from Mexico, risking their lives in the killer heat, hoping to get in. And many people who already live along the border consider themselves under attack by immigrants, and defenseless. Lately in Arizona, the immigration picture has changed so dramatically that I feel as though I'm writing news stories again, not novels.

Q. Who are your writing influences?

A. I got hooked on modern American crime novels when someone gave me a copy of The Underground Man by Ross Macdonald. Later I discovered Robert Parker and Ruth Rendell and Elmore Leonard and so many other great writers. And wonderful new ones come along every year.

The first novelist who captivated me was Graham Greene. I share his fascination with borders and loyalties. Greene liked to quote Browning's line, "Our interest's on the dangerous edge of things, The honest thief, the tender murderer..." That kept coming to mind as I saw what my characters were doing in their time and place. A border between the first world and third world must be the ultimate dangerous edge.

John le Carré still thrills me. Smiley's People and Tinker, Tailor, Soldier, Spy have long been special favorites of mine. I recently discovered that I had never read The Honourable Schoolboy. It was brilliant.

Q. You worked in journalism and you teach it. How do you manage the leap from fact to fiction and back again?

A. Lots of journalists become novelists. Michael Connelly and T. Jefferson Parker did pretty well, I'd say. One currently-working journalist who has written outstanding novels based on his middle east experience is David Ignatius. Reporters and novelists do many of the same things. We observe, we look for telling facts, we set scenes, we try to find interesting people to bring our stories alive. The difference between a responsible journalist and a novelist, I suppose, is that novelists get to make up stuff for their own purposes. Journalists should stick to the facts (and sometimes logical interpretation) for the public's purposes.