Mexico's move to file fraud charges against the country's former oil chief signals that President Miguel de la Madrid Hurtado seriously intends to rail against corruption here.
Several previous presidents have pledged to root out corruption - but only de la Madrid has broken the unwritten rule against charging the highest public officials for possible crimes committed during office.
The accused here is Jorge Diaz Serrano, head of the state oil monopoly Mexican Petroleum (PEMEX) from 1976 to 1981, and a very close friend of former President Jose Lopez Portillo. Mexico's attorney general charges that Diaz Serrano embezzled $34 million in a deal involving the purchase of oil tankers. Diaz Serrano denies the charges.
Mexicans have become increasingly angry about government corruption - but many are skeptical that anything substantial will be done about it. The announcement of charges against Diaz Serrano aroused mostly snickers from Mexico City residents. They say that no matter how guilty, government officials never go to jail.
''I don't believe the charges mean anything,'' said Odilon Moreno, a young factory worker. ''Officials have always stolen, and nothing will change that. It seems to be part of their jobs. I don't think Diaz Serrano will ever go to jail, because his friends in the party will protect him.''
Near the root of Mexico's corruption problem is the same organization that has ensured the country's political stability - the Institutional Revolutionary Party, which has dominated Mexican politics for 54 years. Lopez Portillo, de la Madrid, and Diaz Serrano are all party members. The PRI traditionally selects presidents, and these candidates are automatically elected after a pro forma campaign.
''You cannot really clean the government of corruption because you would have to charge higher-ups, and then the whole political structure would fall apart,'' says Ishmael Ruiz, a clerk, reflecting a typical view of young Mexicans. ''The PRI controls everything in this country.''
Concentration of power in the PRI bred inefficiency, corruption, and nepotism. A spoils system developed, with each president bringing in his own team. So long as they did not challenge the established order, top officials were allowed to use their positions to their advantage, if they chose to.
Under the Lopez Portillo administration (1976-1982), graft and waste were widely believed to have reached new heights. To a large degree, observers say, this is because of the nation's oil boom during his tenure. Huge amounts of money flowed into the nation's coffers, and huge amounts were stolen.
A typical story is related by Humberto Sauri, an engineer: ''I know of one Health Ministry official who, under Lopez Portillo, had about 20 government-owned cars for his personal use. When he was asked by the new administration to turn the cars over, he did - without the engines.''
De la Madrid, who became president last December, campaigned for office on a pledge of moral renovation. He sensed - and tapped - the slow-building anger of Mexicans toward government corruption and mismanagement.
That anger spilled out publicly in February when criminal lawyer Ignacio Burgoa Orihuela of the Chihuahua University Law School and Luis Sanchez Aguilar of the left-wing Social Democratic Party filed a ''citizen's complaint'' with the attorney general.
Orihuela and Aguilar charged Lopez Portillo and his former Cabinet members with ''the misappropriation of $80 billion in foreign loans'' - the amount of the foreign debt when the former President left office.
The charges were dismissed by the attorney general, yet they reflect public bitterness. Mexicans, however, seem to think there is little that will really be done to clean up corruption. And from shoe shiners to taxi drivers to businessmen, many believe the guiltiest person was Lopez Portillo.
There is considerable outrage over the disastrous economic condition the former President left the country - including an inflation rate of 111 percent over the past 12 months - and over the President's inexplicable wealth, estimated here at more than $3 million. (The estimated figure, however, is low compared with some other past presidents.)
One of the first moves by de la Madrid upon taking office was the naming of Gen. Ramon Mota Sanchez as new police chief of Mexico City. The President ordered the general to clean up the department, notorious for its corruption. Police officers reportedly had been expected to daily pay off their supervisers in order to hold their jobs. And many officers have had to ''rent'' their police vehicles from higher-ups. Since the officers generally cannot make such payments from their wages - less than $200 a month - they reportedly extracted bribes fairly routinely from motorists.
The new chief has forbidden the paying of bribes to supervisers. He has held several press conferences outlining steps against corruption and there is a general consensus here that Mota Sanchez means what he says. But while he has been able to make improvements in administration, he has not had as much success in halting bribery. The main obstacles to reform are expected to be habit and low pay. The police chief has not been able to get the funds he wants to increase salaries which, he thinks, would decrease the incentive to engage in corruption.
De la Madrid has also moved to dismantle Mexico City's so-called ''secret police,'' known as the Division of Investigations to Prevent Deliquency (DIDP). Under Lopez Portillo, opposition leaders frequently denounced the secret police, charging that officers committed crimes ranging from extortion to murder.
A recent presidential decree ordered the 2,900-strong force dissolved, charging it was ''operating outside of the law.'' Most DIDP agents were dismissed or reassigned to new jobs within the police department.
Another blot on the government record came with the arrest of Leopoldo Sergio Ramirez Limon, former director of the National Pawn Shop. He was charged with embezzling more than $6.6 million. The Pawn Shop, partly a state-owned organization, is a million-dollar business that serves as a source of cheap loans for thousands of Mexicans.
The administration also passed a code of ethics forbidding government officials to employ or promote relatives. Government officials point to those cases, the code, and the investigation of Diaz Serrano as proof that the administration is intent on fulfilling its promises.
Still, many Mexicans are skeptical that things will really change. ''When Lopez Portillo succeeded President Luis Echeverria Alvarez in 1976, he, too, started office saying he would fight corruption, and he was very popular for a while,'' says Mr. Sauri. ''But then his administration became very corrupt.''
Disillusioned Mexicans will probably have to wait several years to learn if their head of state is following the pattern of his predecessors - or making real progress toward ''moral renovation'' of their country.
Says a local businesman: ''I still have to bribe bureaucrats to do business. So frankly, I'm going to wait until that changes before believing that the government is really fighting corruption.''