A recent study has proposed a new local geometric criterion to evaluate the validity of the Weak Cosmic Censorship conjecture. This criterion applies to thought experiments involving black hole overcharging and overspinning, where the injection of matter could, in theory, transform a black hole into a naked singularity. Weak Cosmic Censorship postulates that such singularities, where classical physics breaks down and predictability is lost, must always be hidden behind an event horizon, preventing their direct observation from the outside.

The method is based on the formation of a closed trapped surface in the horizon cross-section after matter injection, under null convergence and generic conditions. If the resulting final spacetime cannot accommodate this trapped surface, it is ruled out as a physically possible state. This approach allows for the evaluation of whether a black hole can be overcharged or overspun beyond its extremal limit without revealing its singularity.

Applying this criterion has allowed for the exclusion of final states such as superextremal Reissner-Nordström, Reissner-Nordström-de Sitter, and Kerr-Newman black holes, as well as Weyl-class naked singularities. Unlike other methods, this criterion does not rely on asymptotic charges or on a pre-existing extremal condition characterizing naked singularities, making it a more general and robust tool for investigating Weak Cosmic Censorship.