A woman who witnessed her mentally ill father's fatal shooting by police officers—and was only narrowly missed herself—will be able to sue a Texas Ranger who later interrogated her for five hours about the incident without a warrant, the U.S. Court of Appeals for the Fifth Circuit has said.

The background to the Fifth Circuit's recent decision in Lincoln v. Barnes is as follows, according to the opinion:

John Lincoln was diagnosed with bipolar disorder and was taking medication to manage his condition. In December 2013, he ran out of his medication and had been dining with his father when he took a gun and left the house.