McAllen, TX (KRGV) — The death penalty trial of the man accused of killing a San Benito police officer began on Monday.

Rogelio Martinez pleaded not guilty as both sides laid out different accounts of who fired the shots during a 2023 police chase.

Prosecutors told jurors the evidence will show Martinez fired at officers during a high-speed chase that stretched across Cameron County and eventually into San Benito, where San Benito Lt. Milton Resendez was fatally shot.

READ MORE ABOUT THE CHASE HERE.

The defense told jurors Martinez made bad choices that day but argued he was not the person firing at officers. The defense instead pointed to Rodrigo Espinosa-Valdez.

The state's first witness was a park ranger who testified he initially stopped the truck on South Padre Island for speeding. He told jurors Martinez was in the driver's seat and that after a struggle, Martinez got away in the truck.

A constable who later joined the pursuit also took the stand. He described speeds reaching around 100 miles an hour and gunfire during the chase.

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Opening statements are complete and the state has started calling its first witnesses. The constable was still on the stand when the jury broke for lunch; testimony is set to continue in the afternoon.

The judge told jurors the first part of the trial, where they will determine whether Martinez is guilty, could last about a week. If he is found guilty, the case would then move into a separate punishment phase.