The resignation occurred after a controversial determination not to include some works of art as well as a potential decision by the museum to restrict access to the exhibition "Robert Mapplethorpe: Pictures" to visitors under the age of 18. Inaugurated on September 20 and curated by João Ribas, the museum's artistic director for the past eight months, the exhibition includes nearly 159 works by the prominent artist. In a statement given to the newspaper Público, João Ribas said, "The position of director of the Museo Serralves is incompatible with interferences, pressures, and impositions that restrict its technical and artistic independence and translate into inadmissible behaviors that compromise the free expression of works of art or messages, harmonies or logics used by the curator to shape any exhibition like the one featuring works by Robert Mapplethorpe. Limiting the the freedom and independence of the director of the museum is unacceptable." In an open letter addressed to the Fundação de Serralves, a group of leading artists and cultural figures have expressed their opposition to the foundation and their support to the position taken by João Ribas.