Editor’s Note: NGI’s Mexico Gas Price Index, a leader tracking Mexico natural gas market reform, is offering the following column by Eduardo Prud’homme as part of a regular series on understanding this process.

On the last day of January, Mexico’s Supreme Court delivered a verdict that could potentially end President Andrés Manuel López Obrador’s efforts to reshape the country’s energy landscape in his presidential term. The court set a precedent that could have broad ramifications for the electricity market and the intertwined dynamics of natural gas-fueled generation plants by siding with six companies against the electrical reform that López Obrador, or AMLO, strongly supported.

From Supreme Court Minister Luis María Aguilar’s perspective, strengthening public...