Interesting, given that the UK is now doing exactly the opposite by taking away driving licences for migrants with no status (and some who do have status but where the Home Office makes a mistake):

States that let unauthorized immigrants get driver’s licenses make their roads safer for all, a new study suggests.

After implementing one such law in January 2015, California saw a 7- to 10-percent statewide drop in hit-and-run accidents that year, Stanford researchers report Monday in PNAS. That equates to roughly 4,000 fewer hit-and-runs for the year. In that time frame, more than 600,000 unauthorized immigrants got licenses, and the numbers of accidents and traffic fatalities were unchanged by the law.

“Overall, the findings suggest that providing driver’s licenses to unauthorized immigrants led to improved traffic safety,” the authors conclude.

The UK measures are part of Theresa May’s “hostile environment”, which generally involves making people who are already unlawful (but who are not prosecuted) even more unlawful. Over 10,000 licenses have been revoked under the new powers conferred by the Immigration Act 2014 and an inspection report found that hundreds of licenses had been wrongly revoked, causing those involved to be committing the strict liability offence of driving without a license.

Not only has there been no research whatsoever on the effectiveness of the “hostile environment” but forced and voluntary returns are both falling and this research tends to suggest that some of the measures pose a risk to public safety. Evidence based policy this is not.

Source: Letting unauthorized immigrants get driver’s licenses makes roads safer | Ars Technica