Each state has its own criminal penalties for failing to provide accurate information in regards to a motor vehicle accident. Sara, in all likelihood, committed a crime by providing false information to the other driver. I suggest that she contact the services of a criminal defense attorney in Minneapolis, as the police might be setting her up for an arrest. At least get some advice on what she should do as far as talking to the police.
Providing false information to police is a misdemeanor, as is driving without insurance. Misdemeanors carry a maximum penalty of 90 days in jail and up to a $1,000 fine. Failing to provide proof of insurance is also a misdemeanor.
In addition, her driver's license can be suspended if she does not provide proof of insurance when it is requested, if she is convicted of not providing proof of insurance, or if she operates a motor vehicle without insurance.
Several potential criminal charges come to mind: false information to police, leaving the scene of an accident (hit and run), and failure to provide proof of insurance. Gross Misdemeanor crimes have a one-year maximum jail sentence, while simple Misdemeanors carry a 90-day jail maximum.
In the past when I've represented accused of a crime like this, they were charged with the former two (hit and run - property, and no insurance info).
She could consult with a lawyer before talking to police and would be wise to do so. Her lawyer could provide proof of insurance for her, to help protect her.