There isn’t data to answer this question, because it would be incredibly difficult for the state or judicial system to determine whether a driver involved in an accident would have been denied a license renewal under stricter laws.

However, Gordon said he doesn’t think there’s a real threat, because he has faith in Arizona’s medical review program.

“If someone believes there is a driver that is perhaps compromised due to health issues or something else that makes them eligible for having their credential reviewed, there is actually a medical review program that can be done confidentially,” he said.

Gordon said ADOT does not keep statistics on how many medical review requests it receives or how many reviews result in driving restrictions.

The MVD partners with independent medical professionals who make recommendations to the state on whether an individual can safely drive.

“This is something that can be done with family, if you have an elderly person in the family who is reaching a point in life where they may not be the best person to be behind the wheel,” he said. “That’s a very difficult decision, of course.”

The majority of states, including Arizona, do have shorter renewal periods or stricter requirements for older residents because fatal crash rates increase dramatically after the age of 70. And according to the Insurance Institute for Highway Safety, crash rates peak at age 85.

Arizona, with its requirement that drivers over 65 renew their license every five years, doesn’t stand out when it comes to the percentage of drivers 65 or older involved in a fatal crash.

The most recent data from the National Center for Statistic and Analysis shows 13.1 percent of all drivers involved in a fatal crash in Arizona were 65 or older. That’s slightly below the 2016 national average of 13.7 percent.

Thirty-six states have a higher percentage than Arizona, including Maine, where drivers over 65 must renew every four years instead of every six. Additionally, Maine drivers over the age of 62 must take a vision test at every renewal. Still, the state saw one of the highest percentages in the country, with 18 percent of all drivers involved in a fatal crash being 65 or older.

Comparing renewal requirements to crash rates requires the caveat that correlation does not equal causation, and fatal crash rates involving seniors vary widely in states with similar renewal periods and requirements for older drivers.