A Texas appeals court upheld the conviction of green card holder Rosa Maria Ortega for voter fraud on Wednesday, cementing a sentence of eight years in jail and a likely deportation.

Ortega, a mother of four, reportedly thought she was able to vote because she was a permanent resident. She voted five times between 2004 and 2014 — once for the attorney general, Ken Paxton, who later prosecuted her, according to her attorney. She also reportedly served as a poll worker.

Rosa Maria Ortega was convicted of voter fraud. Tarrant County via AP

"She doesn't know. She's got this [green] card that says 'resident' on it, so she doesn’t mark that she's not a citizen,” her attorney told the Washington Post said. "She had no ulterior motive beyond what she thought, mistakenly, was her civic duty."

Prosecutors said that Ortega had correctly told authorities she was a resident alien on a driver's license form, while incorrectly checking the U.S. citizen box for the purpose of voting, undercutting her claims that it was an innocent mistake.

Republicans have claimed that the nation is rife with voter fraud, but credible examples are harder to find, and the handful of cases like Ortega's that are uncovered have faced tough prosecutions and stiff penalties in recent years. Earlier this year, a former felon was sent back to jail for voting illegally while on supervised release from prison.

"This case underscores the importance that Texans place on the institution of voting, and the hallowed principle that every citizen’s vote must count," Paxton said in a statement celebrating the ruling. "We will hold those accountable who falsely claim eligibility and purposely subvert the election process in Texas."