Editor's note: Ruben Navarrette is a CNN contributor and a nationally syndicated columnist with the Washington Post Writers Group. Follow him on Twitter: @rubennavarrette.
(CNN) -- I keep thinking of those television ads from the Mexican tourism industry urging Americans to "Come visit Mexico."
Visiting isn't difficult. For some Americans, it's leaving that's the problem.
For years, U.S. officials have urged their Mexican counterparts to get tough on drug traffickers. The Americans even provided $1.4 billion through the Merida Initiative to help our friends south of the border accomplish that goal.
Yet, the drama that unfolded in the state of Sonora for the last week can't be what U.S. officials had in mind.
The idea was to help Mexico's police and military pursue violent criminals -- the sort who terrorize people by scattering human heads like party favors on the dance floors of nightclubs -- not to prey on Americans held for ransom by crooked cops looking for their next payday.
And that seems to be what happened to Yanira Maldonado, a 42-year-old U.S. citizen who spent the last several days sitting in a women's prison in Nogales, Mexico, on what looks like bogus drug charges.
Maldonado, a Mormon with seven children and two grandchildren, was released late Thursday when a judge concluded what was already evident to most of us -- that the Mexican authorities had no evidence to hold her.
The family's nightmare is over. It began last week when the Mexican-born Yanira and her husband, Gary, boarded a bus to head back to the United States after attending her aunt's funeral in Mexico.
That was their first mistake. Those of us who visit Mexico know you never get on a bus. It makes you easy pickings for bandits and bad cops, and sometimes you can't tell the difference. Bandits might take your money, and let you go on your way. Bad cops take your liberty, and hold it until someone back home sends enough money to let you go on your way.
Either way, it's not personal. It's just a business transaction. But it's a cruel and ugly business.
Anyway, back to the bus. It came up to a military checkpoint -- which might as well be a toll booth -- and everyone was taken off the bus as soldiers boarded it.
"I was at the checkpoint, asked to get off bus," Yanira told CNN from prison. "They were checking for drugs and I don't know what else. They say they found something under the seat but I never saw anything. They didn't show me anything. It was amazing all what they did."
The soldiers claim that they found a package containing 12.5 pounds (5.7 kilograms) of what appeared to be marijuana under Yanira's seat. And so they placed her under arrest, and handed the case over to the Mexican attorney general's office for prosecution.
Maybe drugs were there before she ever sat down. Or maybe the soldiers put the drugs there. Or maybe there were no drugs at all. No one knows, because, conveniently, the only people on the bus were the soldiers.
Gary Maldonado has said that he and his wife checked their bags, and boarded with no luggage. He says that when his wife was taken into custody, one of the soldiers told him matter-of-factly that it would cost him $5,000 to get her released. Later, according to family members, he was quoted the same price by civilian authorities -- $5,000 -- for her release, whether she was found guilty or not.
That's how it works. Think of it as a processing fee.
In Mexico, stories like this one -- which are all about money, and corruption, and how predatory some hungry people can be when they catch a glimpse of a piece of bread -- are as common as pinatas and margaritas.
But that's not supposed to be the case anymore.
I was in Mexico City in November on a mission sponsored by the American Jewish Committee. We met with top officials, including President Enrique Pena Nieto, and the message could not have been clearer. "With a booming economy, less crime in metropolitan areas, and the reins of power now back in the hands of the Institutional Revolutionary Party, the country is open for business. This is the new Mexico."
Sorry folks, it seems there are still unseemly remnants of the old Mexico, and they are threatening to undermine the makeover.
The Maldonados probably aren't thinking about the relationship between the United States and Mexico at the moment. They're just glad to have a wife and mother home with her family.
This ugly chapter, in their lives and in the U.S.-Mexico relationship, is finally closed.
Incidentally, Mexico is still waiting on the last few hundred million dollars in drug fighting funds promised under the Merida Initiative.
Congress should send the rest of the money. Minus $5,000. That should go to the Maldonado family. Think of it as a processing fee.
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The opinions expressed in this commentary are solely those of Ruben Navarrette.