Originally from Middletown, Pennsylvania,[1][2] McNair graduated from Gettysburg College in 1900, earned a law degree from the University of Michigan in 1903, and became an attorney in Pittsburgh in 1904.

[citation needed] During his fractious leadership McNair even set up his office in the ornate lobby of the City-County Building to display his "independence" from council and the city bureaucracy.

[2] He continued to be a lightning rod during his administration, being arrested at one point for refusing to return what a judge found to be an unlawful fine he had assessed a citizen.

[4] Later when he received word that the governor was considering impeachment proceedings against him he installed a bed in the mayor's office and conducted press conferences from it.

[citation needed] The most fateful event for his political career took the city by force on Saint Patrick's Day 1936 when it suffered from the worst flooding in its history.