While Mark Hebert, 48, isn't directly charged with killing Albert Bloch, both federal and state investigators identified him as a murder suspect, The Times-Picayune newspaper in New Orleans reported.
Hebert was charged Monday with a series of federal crimes, including violating Bloch's civil rights, bank fraud, computer fraud and identity theft.
The office of U.S. Attorney Dana Boente said that Hebert "with specific intent, did kill, or participate in conduct that caused the death of, Albert Bloch."
Hebert was a Jefferson County sheriff's deputy in 2007 when Bloch, a Metairie, LA., resident, was involved in a one-vehicle accident. Investigators say that while Bloch was hospitalized, Hebert obtained his debit card and drained his bank account.
After Bloch got out of the hospital, he complained to the bank about the charges on his card and obtained a new one. Bloch was last seen in Hebert's company, investigators say.
Hebert was later sent to prison for stealing from another motorist in 2008.
Both federal and state authorities have said they don't know what happened to Bloch but are certain he was killed by Hebert.
"We believe that Mark Hebert had something to do with not only his disappearance and what we believe is his ultimate murder," Jefferson Parish Sheriff Newell Normand said Monday.
Davidson Ehle, Hebert's lawyer, said the Jefferson Parish district attorney decided in 2010 not to charge Hebert with defrauding Bloch.
"We've been through this before," he said. "Unfortunately, the United States decided to charge him after we believed that these charges were resolved."