When the fingerprint results come in, they confirm the prints were Talbot's on the safe. Talbot never touched the safe.
The Highway Patrol only investigates crimes and/or offenses that occur on the state highway system, and in some states, they help to investigate auto thefts. They do not investigate crimes that occur off the highway system, such as in this episode when a jewelry store in mid-city is robbed. That would be investigated by city or county police.
The squad car used in the roadblock changes from a '56 Oldsmobile 88 to a '56 Mercury Custom and then back into the Olds.