The decision of the superior court refusing to grant a writ of mandate may be reviewed by the supreme court within five days after the decision of the superior court. The review must be considered an emergency matter of public concern, and be heard and determined with all convenient speed. If the supreme court decides that the petitions are legal in form and apparently contain the requisite number of signatures of legal voters, and were filed within the time prescribed in the Constitution, it shall issue its mandate directing the secretary of state to file the petition as of the date of submission.