Evidence presented in court Monday suggests that nearly 40,000 people were victimized in an elaborate skimming scheme.
Aleksandr Goukasian is accused of placing debit card skimming devices in gas pumps across North Texas to illegally capture people's account information.
Goukasian faces up to 99 years in state prison if convicted on the identity theft charges. In a deal last year with federal prosecutors, he pleaded guilty to a charge of using an unauthorized access device.
In court, prosecutors spent much of the day trying to tie Goukasian to a similar case in Houston. Devices recovered there in March 2011 had the same unusual markings as those found in Dallas and Las Vegas. Prosecutors say files on a laptop connect all three cases.
The state rested its case late Monday.
Goukasian's defense team said it would likely call only one witness when testimony resumes Tuesday morning.