"Now they realize it will never end," the consultant said. "They feel like prisoners."
(Government and private security experts discussed several cases with The Times on condition that the victims not be identified.)
At the Ciudad Juarez store of a big international hardware chain, extortionists called the manager and demanded $50,000. He quickly left the store, only to be intercepted by the callers and held in the trunk of their car for three hours before being released.
"Next time, we kill you," they told him.
Instead of paying, he did what many entrepreneurs are doing: He closed the store and left the country.
The number of Mexican businessmen transplanting themselves, and often their businesses, to the United States has grown enormously in the last five years, as measured by so-called investment visas issued by the U.S. government to wealthy Mexicans, and by the millions of dollars those Mexicans are investing in new enterprises north of the border.
Businesses' flight represents a serious blow to Mexico's struggling economy, in terms of lost investment, lost tax revenue and lost jobs.
A study last year by the Bank of Mexico found that more than 60% of Mexican businesses said they had been hurt by the national climate of lawlessness, with extortion counting as one of the prime factors. Production losses totaled 1.2% of gross domestic product, the study found.
The construction industry is also suffering.
At a shopping mall under construction on the outskirts of Mexico City, the extortionists knew to hit their target on a Saturday: pay day.
With the masons, electricians and plumbers cowering at the back of the site, the extortionists, claiming to be members of the notorious La Familia cartel, said they would open fire on anyone who tried to leave unless they were paid. In that case, according to people involved, the police arrived and arrested the assailants, a rarity. More often, construction foremen routinely make payments to a bag man who arrives weekly or monthly.
Jose Eduardo Correa Abreu, president of the Mexican Chamber of Construction Industry, said the problem has become so bad that in some states, such as violent Guerrero, builders have stopped taking on certain projects.
It's not just the business sector.
Last month, priests from 19 Roman Catholic parishes in the state of Mexico, which surrounds this capital, went to authorities to beg for protection from gunmen who appeared at their churches and demanded monthly payments.
"They were terrified," said David Castañeda, mayor of Atizapan. Threatening priests "is a sensitive point for society."
The priests, from the area where The Rat was working, had reason to be terrified: A couple of weeks earlier, Father Genaro Aviña was found beaten and shot to death in the sanctuary of his Immaculate Conception Church. The extortionists warned that Aviña was the example.
Local authorities installed "panic buttons" in the churches for the priests to call for help next time the gunmen showed up.
A year earlier, priests and evangelical preachers in Michoacan, President Felipe Calderon's home state, reported that they were forced to pay extortionists in order to hold religious holiday festivals.
In Acapulco, thousands of schoolteachers refused to report to their classrooms last fall after extortionists demanded that they fork over part of their salaries. The threats came in letters delivered to the teachers, on signs hung outside the schools and, in a few cases, from men who burst into schools. Much of the school system was paralyzed for months, until the federal government sent troops into the region.
"As a crime, extortion has become totally indiscriminate," Seoane, of Pinkerton, said. "In a country like Mexico, it's easy to trade on fear."