Christhian Bahena Rivera, the man accused of murdering Mollie Tibbetts, stayed relatively quiet for years in the small town in Iowa where he worked at a family dairy farm.
His employer, Yarrabee Farms, is saying Rivera presented himself as a legal U.S. resident and reliable worker.
Rivera was an employee for the family farm for the last four years where he allegedly worked under a different name. His stunned employers said Rivera was a "good employee who helped take care of their cows and got along with co-workers."
Rivera continued to go to work after Tibbetts was pronounced missing and his employers say they did not notice a change in his demeanor.
"Our employee is not who he said he was," owner of the farm Dane Lang said at a news conference. "This was shocking to us."
Lang said the farm had received dozens of disturbing phone calls and messages since the announcement of Rivera's arrest. People have called and left voicemails threatening to kill his dog and burn down his buildings.
According to lang, Rivera was hired in 2014 where he presented an out-of-state government-issued photo identification and a matching social security card. That information was allegedly run through the Social Security Administration's employment-verification system and checked out, he said.
Rivera's defense attorney, Allan Richards, said he was prepared to argue that his client was in the country legally. He argued that his client came to the U.S. as a minor and had worked and paid taxes for years.
"He showed up every day and he did his job. He was patted on his back. They turned a blind eye to the reality of documentation," Richards said.
Immigration and Customs Enforcement officials have lodged an immigration detainer for Rivera.
Rivera faces life in prison and has a bail of $5 million cash-only bond.