I let my relative use my car who then hit another car. He was arrested and charged with DUI. Can I get sued for lending him my car?

You may because you lent the car (it sounds like) to someone you knew was drinking, you provided the alcohol.  Here are some laws to look at. Have you been contacted by an insurance company/cited by police?

    471.410 Providing liquor to person under 21 or to intoxicated person; allowing consumption by minor on property; mandatory minimum penalties. (1) No person shall sell, give or otherwise make available any alcoholic liquor to any person who is visibly intoxicated.

      (2) No one other than the person’s parent or guardian shall sell, give or otherwise make available any alcoholic liquor to a person under the age of 21 years. A person violates this subsection who sells, gives or otherwise makes available alcoholic liquor to a person with the knowledge that the person to whom the liquor is made available will violate this subsection.

      (3) No person who exercises control over private real property may knowingly allow any other person under the age of 21 years who is not a child or minor ward of the person to consume alcoholic liquor on the property, or allow any other person under the age of 21 years who is not a child or minor ward of the person to remain on the property if the person under the age of 21 years consumes alcoholic liquor on the property. The prohibitions of this subsection apply only to a person who is present and in control of the location at the time the consumption occurs. The prohibitions of this subsection do not apply to the owner of rental property, or the agent of an owner of rental property, unless the consumption occurs in the individual unit in which the owner or agent resides.

      (4) A person who violates subsection (1) or (2) of this section commits a Class A misdemeanor. Upon violation of subsection (2) of this section, the court shall impose at least a mandatory minimum sentence as follows:

      (a) Upon a first conviction, a fine of $350.

      (b) Upon a second conviction, a fine of $1,000.

      (c) Upon a third or subsequent conviction, a fine of $1,000 and not less than 30 days of imprisonment.

      (5) The court shall not waive or suspend imposition or execution of the mandatory minimum sentence required by subsection (4) of this section. In addition to the mandatory sentence the court may require the violator to make restitution for any damages to property where the alcoholic liquor was illegally consumed or may require participation in volunteer service to a community service agency.

      (6) The mandatory minimum penalty provisions of subsection (4) of this section shall not apply to persons licensed or appointed under the provisions of this chapter.

      (7) A person who violates subsection (3) of this section commits a violation. Upon violation of subsection (3) of this section, the court shall impose at least a mandatory minimum fine as follows:

      (a) Upon a first conviction, a fine of $350.

      (b) Upon a second or subsequent conviction, a fine of $1,000.

      (8) Nothing in this section prohibits any licensee under this chapter from allowing a person who is visibly intoxicated from remaining on the licensed premises so long as the person is not sold or served any alcoholic liquor. [Amended by 1963 c.243 §1; 1971 c.159 §5; 1977 c.458 §1; 1977 c.814 §1; 1983 cor. c.736 §1; 1995 c.301 §40; 1995 c.599 §5; 1995 c.756 §1; 1999 c.351 §58]

30.135 Liability of certain persons that lend, rent, donate use of, make available for test drive or otherwise provide motor vehicle. (1) Subject to the provisions of this section, a person that lends, rents, donates use of, makes available for test drive or otherwise provides a motor vehicle, as defined in ORS 801.360, to another person is not liable for any injury, death or damage that arises out of the use of that motor vehicle by the other person, unless the person providing the motor vehicle is negligent in maintaining the motor vehicle or in providing the motor vehicle and the injury, death or damage results from that negligence.

      (2) The limitation on liability provided by this section applies only if the person providing the motor vehicle is engaged in the business of selling, renting, leasing or repairing motor vehicles and the motor vehicle is provided to another person in the course of that business.

      (3) The limitation on liability provided by this section applies only if there is a written agreement between the person providing the motor vehicle and the person receiving the motor vehicle, and the agreement specifically indicates that the person receiving the motor vehicle is liable for any injury, death or damage arising out of the use of the motor vehicle. The limitation on liability provided by this section applies to injury, death or damage suffered during the period specified in the written agreement, or until the return of the motor vehicle, whichever is later.

      (4) The limitation on liability provided by this section applies without regard to whether the motor vehicle is provided for consideration or is provided without charge.

      (5) Nothing in this section affects the liability of a manufacturer, distributor, seller or lessor of a product under the provisions of ORS 30.900 to 30.920.

      (6) Nothing in this section increases, reduces or relates to those obligations that a self-insurer may choose to undertake pursuant to ORS 806.130. Nothing in ORS 806.130 increases, reduces or relates to the limitations of this section. [1999 c.438 §1; 2001 c.291 §1; 2003 c.331 §1; 2007 c.287 §4]