DESPITE COCKAMAMIE conservative conspiracy theories, actual cases of intentional or even possibly intentional voting fraud are so rare in the United States that when one does crop up, Republicans get themselves in a lather. That explains the ugly tone of self-righteousness and retribution attending the scapegoating of Rosa Ortega, whose sentence of eight years in prison for voting illegally in Texas is a travesty of justice.

Eight years, really? That falls in the midrange of sentences for second-degree felonies in Texas, which include manslaughter, aggravated assault, sexual assault, possession of up to 2,000 pounds of marijuana and human trafficking. It’s a draconian and absurdly severe punishment for Ms. Ortega, who has a sixth-grade education and guilelessly exposed her intention to cast an illegal vote to elections officials.

Ms. Ortega, 37, has lived most of her life in Texas. As a legal permanent resident of the United States, she is eligible to work, serve in the military, pay taxes and receive most public benefits. But her green card does not entitle her to vote; therefore she committed a crime by having done so while living in Dallas County in 2012 and 2014.

Generally speaking, illegal voting has been punished in Texas by a short prison sentence or even just probation. In the case of Ms. Ortega, however, Texas’s Republican attorney general, Ken Paxton, was only too happy to scapegoat her by means of what he called a punishment that “sends a message that violations of the state’s election law will be prosecuted to the fullest.”

Mr. Paxton has been part of the chorus of Republican officials nationwide, including President Trump, who have conjured up the specter of fraudulent ballots cast by Democratic voters on a massive scale — despite the fact that not a shred of evidence exists to support that view and that study after study has refuted it. The GOP was determined to make an example of Ms. Ortega, even though she voted for Republicans.

Ms. Ortega has a family full of U.S. citizens, including her four teenage children and two brothers, all born in Texas. She says she believed she was eligible to vote, having done so without difficulty in Dallas County after checking a box saying she was a citizen. After moving to an adjacent county, her voter registration application was rejected after she checked a box affirming she was not a citizen. She then called election officials to say she’d previously voted with no problem, and asked for another application, this time checking the box asserting that she was a citizen. That tipped off officials, who arrested her on fraud charges.

For now, Ms. Ortega is out of jail on appeal. It is conceivable that her sentence will be reduced, as it should be if Texas courts have any sense of proportion. However, she is also likely to be deported after serving whatever term she ultimately receives, and separated from her family. That, too, would be an injustice.