By Pam Zekman

CHICAGO (CBS) — City workers are expected to be efficient about doing their jobs, but a recent CBS 2 investigation found it was taking three city workers to change a light bulb – with one of those workers sitting down in a chair the whole time.

On Wednesday, 2 Investigator Pam Zekman asked Mayor Rahm Emanuel the question everyone wanted to know: how many city workers does he think it should take to change a light bulb?

“There is such a rich joke there its appropriate I stay away from it,” Emanuel said, after he stopped laughing.

Banquet hall operator John Kapusciarz wasn’t laughing when he saw a crew of three city workers changing light bulbs in an alley behind his business. He took pictures and sent CBS 2 an email asking “How many city of Chicago employees does it take to change one light bulb?”

It turns out, it takes three city workers to change light bulbs in street and alley lights, due to union work rules.

Those work rules require a $70,000 a year truck driver to drive the city truck to the work site and two other $85,000 a year workers – one to go up in a cherry picker to change the bulb and another required on the ground for safety.

When Kapusciarz watched the crew at work, he saw one of the three workers pull out a chair and sit around the entire time.

“It makes me very, very mad, because it’s my money that I’m paying in property taxes,” Kapusciarz said. “Where does this nonsense end?”

He said he’s seen the same task done by a one-man crew from a private company working for Walgreens.

“One guy, one truck. One guy can get the job done,” Kapusciarz said.

But Emanuel hedged when pressed on whether the city should also use only one worker to change light bulbs on street and alley lights.

“I’m not going to talk about how many of this and how many that,” Emanuel said. “But work rules do not trump workers when there are common practices throughout the workplace of America.”

We weren’t able to catch up with the mayor for further comment, but later his press secretary did say the mayor plans “to take a top to bottom look at the way the city does its business so it can be done more efficiently for taxpayers.”

Late Wednesday afternoon, Kapusciarz got a call from the city inspector general’s office, asking about the photos. He said he’s sending the photos to the inspector general and providing details on what he saw.

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