FORT WORTH, Texas (AP) _ A businessman cleared of criminal charges in the shooting death of his 12- year-old stepdaughter took the stand today in a civil case brought by his ex- wife and said she was mistaken in identifying him as the gunman.

Cullen Davis was called by attorneys for Priscilla Davis as an adverse witness in a surprise move.

Mrs. Davis and her former husband, Jack Wilborn, are suing Davis for more than $21 million in connection with a 1976 shooting spree at Davis's mansion that left two people dead, including Mrs. Davis's daughter, Andrea Wilborn, and two others injured.

Davis was questioned by Mrs. Davis' attorney, Bob Gibbons, about an incident in which some kittens were killed.

''Were you in a rage when you killed the kitten?'' Gibbons asked.

''I was mad. I don't know about a rage. I knew what I was doing,'' Davis said, terming the incident stupid.

Gibbons later asked Davis if Mrs. Davis was correct in saying she knew Davis's voice at the time of the shooting.

''Not if she was placing me at the scene of the crime,'' Davis said.

Davis said he was not mad or bitter toward Mrs. Davis on the day of the shootings.

''I was frustrated,'' he said.

At the time, Davis faced $14 million in personal debts and the judge overseeing his divorce from Mrs. Davis had ordered his alimony payments raised and ordered him to advance thousands of dollars for her debts and attorneys.

The civil trial going on in Fort Worth differs substantially from Davis' previous criminal trial.

In what then was the longest, costliest murder trial in Texas history, an Amarillo jury acquitted Davis of killing his stepdaughter.

Mrs. Davis was wounded, her boyfriend Stan Farr was killed and a young mansion visitor, Bubba Gavrel, was permanently disabled in the shooting spree by a bewigged gunman dressed in black.

Gavrel's date, Beverly Bass, 18, was the only person to escape the mansion unharmed.

The three survivors testified in Amarillo that Davis was the gunman.

Last week, they told their stories again, this time without interruption by scores of objections and without the intense cross-examination by the defense.

Davis himself did not testify in Amarillo.

Under the rules governing civil cases, lawyers for Mrs. Davis are not required to prove guilt beyond a reasonable doubt but by the less strenuous preponderance of evidence.