The nine would allegedly arrive at the National Museum of Folk Arts and Traditions in the capital's EUR district, and clock on before spending the rest of the day on more agreeable pursuits, returning at the end of their shift to clock off, police said.
One woman would spend the day at her husband's fruit and vegetable stall, while others went for a flutter or two at a nearby betting shop.
An investigation got underway last February, with police setting up video cameras to catch the workers cheating the time management system.
They are now being probed for forgery, defrauding the State and perjury.
The latest case of chronic absenteeism comes after police revealed last September that nearly three out of four employees at San Remo town hall abandoned their work duties each day.
They included one who spent much of his work time indulging his passion for canoeing yet still regularly filed overtime claims.
The astonishing scale of absenteeism came to light after police were tipped off about the problem and organized a surveillance operation covering 272 of the town hall's 528 staff.
Some 196 of those monitored, or 72 percent, were guilty of "frequent irregularities".