Practices of public procurement and the risk of corrupt behavior before and after the government transition in México

Corruption has a huge impact on economic growth, democracy, inequality, and its consequences at the human level are incalculable. However, a government turnover may be expected to generate significant changes in the way public contracting is done, and thus, in the levels and types of corruption involved in public procurement. In this respect, M\'exico lived a historical government transition in 2018. In this work, we analyze data from more than 1.5 million contracts corresponding from 2013 to 2020, to study to what extent this change of government affected the characteristics of public contracting, and we try to determine whether these changes affect how corruption takes place. To do this, we propose a statistical framework to compare the characteristics of the contracting practices within each administration, separating the contracts in different classes depending on whether or not they were made with companies that have now been identified as being involved in corrupt practices. We found that, even when the total number of contracts and the amount of resources spent in contracts with corrupt companies decreased after the government transition, many of the patterns followed to contract suppliers labeled as corrupt were maintained, and those in which changes did occur, are suggestive of a larger risk of corruption.