Kassandra Martinez's future just got even bleaker.

The 20-year-old Mexican national was already in jail on a murder charge for allegedly running over her cousin last month at a Northwest Dallas gas station. Witnesses told police Martinez was mad at the cousin for refusing to chip in for gas after a trip to Viviana's Nite Club off Stemmons and Northwest Highway. When the cousin went to retrieve her purse from the car's trunk, Martinez threw her Volkswagon Passat in reverse, backed over Yunuel Aguilar, then ran over her again on her way out of the parking lot.

See also Police Say Kassandra Martinez Ran Over Her Cousin after She Wouldn't Chip in for Gas

A recently completed autopsy has added another wrinkle to the case: Aguilar was pregnant. As The Dallas Morning News' Scott Goldstein reports, this has led prosecutors to charge Martinez with capital murder.

The Prenatal Protection Act, a law passed by the state legislature in 2003, extended the protections of the criminal code to include unborn children. Killings are classified as capital murders in many circumstances, including when the victim is younger than 6, as a fetus certainly is.

So, instead of facing as little as five years in prison for a simple murder charge, Martinez could get the death penalty if convicted. All for a few bucks of gas money.