José “Pepe” Merino, 46, led Mexico City’s data agency. “Homosexual, atheist, socialist, political scientist,” declared his Twitter bio. He was an outspoken defender of transparency in a country still shadowed by its authoritarian past. As an academic, he’d founded the data blog at Nexos back in 2016. The next year, he led an audacious effort to extract information from a government database of 32,000 disappeared people. Then he embraced the leftist movement of Andrés Manuel López Obrador, who won the presidency in 2018.