All other Chief Justices, except for Victorino Mapa, were incumbent Associate Justices at the time of their appointment as Chief Justice. Mapa had served as Associate Justice from 1901 to 1913, when he was appointed as Secretary of Justice.
The other Chief Justices, with the exception of Victorino Mapa, had prior experience as current Associate Justices when they were appointed to the position of Chief Justice. Mapa's tenure as an Associate Justice from 1901 to 1913 came before his appointment as Secretary of Justice.