The 1975 staffing spreadsheet of HM Prison Pentridge provides a detailed operational portrait of the prison complex in the mid-1970s. Developed by a roster clerk — one of the very few civilian personnel employed at the time — the document is entirely handwritten. In 1975 there was no access to computerised Excel-type spreadsheets, and all rostering was done manually.

The spreadsheet identifies every operational post required to open, secure and manage the Coburg complex. In many respects, it offers an ideal picture of how the prison operated on a daily basis.

Donated to the Pentridge Prison online Museum by Greg Howden.

At the time of its production:

• Governor Gill oversaw the Southern Prison

• Governor Bert Buckley governed the Central PrisonGovernor Charlie Taylor was in charge of the Northern Prison

Three Prisons Within One

In the mid-1970s, Pentridge was divided into three distinct sections:

Northern Prison - Comprised A Division, J Division, and H Division.

Central Prison - Comprised B Division and E Division.

Southern Prison - Comprised D Division, F Division, and G Division.

This structure shaped the allocation of staff across the complex and is clearly reflected in the roster  .

Each division had a defined operational role — from the remand population in D Division, to the Young Offenders Group in J Division, to the high-security and difficult prisoners in H Division.

Notably, the spreadsheet makes no reference to Jika Jika (later renamed K Division). This is because Jika Jika was not commissioned until 1978. Its absence confirms that the roster captures Pentridge in its pre-modern configuration.

Staffing in a Large Prison

At the time the spreadsheet was developed, HM Prison Pentridge housed approximately 1,100 to 1,200 prisoners. By contemporary standards, staffing levels were very lean.

With roughly 396 staff managing a prisoner population of over a thousand men, officers were required to cover towers, divisional posts, escorts, court duties, records offices, perimeter security, industries and administrative roles. The Supreme Court and the County Court were staffed by officers assigned to the Southern Prison. The ‘D’ Records Office and the Front Office in the Central Prison were entirely staffed by uniformed officers. There were very few civilian staff employed in the prison.

A Uniformed, Hierarchical Service

Pentridge in 1975 was almost entirely a uniformed service. Officers manually maintained prisoner records, calculated release dates from court warrants — sometimes referred to as “the black art” — managed prisoner accounts and property, and processed bails and fines without computer assistance  .

The roster clerk, though a civilian without direct command authority, was central to operations. Working from the Governor’s or staff office, he created complex cyclical rosters and allocated daily staffing, including overtime.

Assignments were made through a strict chain of command. Officers did not choose their divisions; roles were allocated by senior officers. “Lockers” — Bottom, Middle and Top — were experienced officers responsible for leadership within each division.