An off-duty California Highway Patrol officer faced the ultimate test of conscience recently when she came across two large bank bags sitting in the middle of the street as she made her way home.

"I opened [one of the bags] enough just to see that it was $100 bills," she told ABC News affiliate KGO-TV in San Francisco.

What the officer, who asked to remain anonymous, had come across in Concord, California, on Monday, was $120,000 in cash - and no one around to claim it.

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"I was like, 'Oh my God,'" she said. "It didn't feel real."

The officer turned the bags in even though she said she was facing financial struggles to make ends meet with her family.

"My kids, when I came home, were like 'Mom, what were you thinking?'" she said.

In May, three upstate New York roommates found $40,000 stuffed in a sofa they'd gotten from a thrift store. They tracked down the couch's previous owner and returned every dollar to her.

And in Boston, a homeless man turned in a backpack containing $42,000 in cash and traveler's checks in September 2013.

In Concord, California, authorities eventually gave the money to a man who had reported losing his life savings.

The officer said that she hadn't considered keeping the money for herself and that she planned to use the experience to teach her children a lesson.

"Nobody would have known [about the money]," she said, "but that's what determines a person's integrity. It's what you do when nobody is looking."