The former water department supervisor was found guilty Monday on all 11 charges after a short deliberation. Jurors received the case on Friday around noon.
After the jury announced its verdict, Neubauer offered a limited apology and suggested that others should have been placed on trial.
"Yes, I do apologize for what happened, but I would also like to add that it was none of my decision, it was never any part of my plan," Neubauer said.
Neubauer worked her way up from a low-level clerk to Crestwood's police chief, but it was her action -- or inaction -- as a Water Department supervisor that led to her conviction Monday on 11 counts of lying to the government.
Neubauer signed off on documents claiming that Crestwood's water supply was safe and 100 percent from Lake Michigan.
The reality, though, was that Crestwood was supplementing its Lake Michigan water with water from a city well that state officials determined contained chemical compounds linked to cancer.
Neubauer claimed she was simply a low-level clerk with little power and little understanding of the numbers on the documents she signed.
Neubauer's defense: I did what the higher ups told me to do.
"I was on the bottom of the food chain, just there to do my job," said Neubauer. "How they were able to twist things around and all of a sudden, Theresa Neubauer, the water clerk, must have ran the whole town of Crestwood, because I'm the only one standing here today answering for these charges."
Neubauer is referring to now-retired longtime mayor Chester Stranczek, who is said to be suffering from mild-to-moderate dementia and was never charged in the Crestwood water scandal.
Prosecutors did not discuss Stranczek, but said Monday the issue at trial was clear: Neubauer knew what she was doing and she lied about it.
Safe drinking water is one of those very fundamental things, that there should be no exceptions to these rules," said Assistant U.S. Attorney Timothy Chapman. "And there should never be exceptions to these rules."
Monday's verdict is a form of vindication for whistleblower Tricia Krause, who spent the last two decades arguing that tainted groundwater in the area has led to higher than normal cancer rates.
"When you have a job and you don't question things, that's wrong," said Krause. "And you knowingly knew the well was being secretly used, was wrong."
The Village of Crestwood maintains to this day that its water was and remains safe to drink.
Three years ago, the Illinois Department of Public Health concluded that there were higher than normal cancer rates in the Crestwood area and it suggested that a chemical compound in the water could be a contributing factor, but it could not be definitively determined.
Officials drew water from the tainted well until 2008 even though environmental officials warned that cancer-causing chemicals had oozed into the well as early as the 1980s.
Dozens of lawsuits blame the well for illnesses, including cancer.Neubauer's sentencing date is tentatively set for October 2.