An opaque and creaky court system groans under the weight of thousands of new drug war cases, and a number of prosecutors, defense lawyers and judges have been slain. Meanwhile, prison officials scramble to make room for the surge of detainees, many of them violent.
Calderon's administration has laid out a strategy to expand and revamp the federal police and to force states, cities and towns to modernize and clean up their forces through such tools as polygraphs and drug tests. Standing in the way are many years of graft, turf jealousies, budget constraints and a drug underworld that has greeted every government move with greater viciousness.
Garcia Luna, the public safety chief, has seized the moment to hire thousands of federal cadets, who under the strict new standards must hold at least a university degree. Despite the stiff requirements, the federal force has grown to 32,264 officers, from about 25,000 a year ago.
At a sleek federal campus here in the north-central state of San Luis Potosi, Mexican officials are rushing to turn 9,000 college graduates into federal investigators. The school boasts state-of-the-art lecture halls, computer rooms, workout facilities, a driver-training track and shooting range.
The U.S. government supports the push to expand and professionalize Mexico's federal forces, lending dozens of police instructors as part of a $1.4-billion aid package for Mexico known as the Merida Initiative.
Federal cadets, dressed in white polo shirts and smart bluejeans, study criminal procedure, interview techniques, criminology and intelligence. The school has graduated 2,234 investigators since June; more than 1,000 fresh recruits began the six-week course last month.
An even more daunting challenge waits in states and cities, which are home to the vast majority of police in Mexico -- more than 370,000 officers. In the last two years, the federal government has relied on budget incentives to prod local departments to vet officer candidates and boost salaries, now often as low as $90 a week.
Garcia Luna has gone so far as to call for eliminating the country's 2,022 municipal agencies, widely seen as the weakest link in Mexican law enforcement, and folding them into police departments of the 31 states and Mexico City, which is formally a federal district.
The proposal is controversial, probably requiring a change in the Mexican Constitution and facing opposition from municipal officials from across the political spectrum who are reluctant to yield parts of their fiefdoms.
Some analysts warn that such a plan could make it easier for criminal groups to bribe police.
"Concentrating power at the state level runs the risk of creating a more hierarchical, 'one-stop-shopping' system of high-level corruption," said David Shirk, a University of San Diego professor and a fellow at the Woodrow Wilson Center in Washington.
States and municipalities have moved inconsistently to clean up their forces. In some places, such as the northern city of Chihuahua, police are gradually adopting U.S.-style law enforcement standards, such as those promoted by the private Commission on Accreditation for Law Enforcement Agencies.
Many analysts are encouraged to see local agencies spending more to improve training, equipment and wages, but see scant improvement on corruption.
"You can train police all day long, but if they're still corrupt, then it doesn't really help," said Daniel Sabet, who teaches at Georgetown University and studies Mexican law enforcement. "The corruption and organized-crime infiltration has not changed."
Here in San Luis Potosi state, whose police operation is praised by the U.S. as among a handful in Mexico that are sound, officials raised minimum pay to about $700 a month and now offer bonuses of nearly two months' pay to officers who perform well and pass twice-yearly vetting.
Cesareo Carvajal, public safety director until the state government changed hands in September, said he fired about 150 of 3,000 officers during his two-year term.
The agency also bought radio equipment, new weaponry and police vehicles, and outfitted officers with redesigned uniforms to create an updated image.
At a state-run police academy where San Luis Potosi's next generation of police is being molded, the rhythmic thump-thump of boots on pavement echoed on a recent morning as officers-in-training practiced marching.
Cadets here say a new, trustworthy breed of Mexican police is possible -- but that it will take time to build.
As part of a stricter selection process, recruit Hiram Vinas was hooked to a lie detector and asked about any past scrapes with the law. Screeners peeked into his bank account and rummaged in his family's background.
Vinas, 24, wearing a blue windbreaker and buzz cut, said the rigorous scrutiny could help win over Mexican society.
"They are applying tests and evaluations now that had never been done in our country," he said. "I think over time, people will learn to trust the police again."