The legal trials and tribulations that have plagued T. Cullen Davis, 46, since he bitterly parted ways with his ex-wife five years ago ended today when the Fort Worth multimillionaire was acquitted of charges of masterminding a murder-for-hire scheme.

Jurors who acquitted Davis after 15 hours and 29 minutes of deliberation said there was never any doubt in their minds that the defendant was innocent.

Davis was shaking when presiding Texas District Court Judge Gordon Gray read the verdict at 11:25 a.m. Davis and his chief defense attorney, Richard (Racehorse) Haynes, burst into tears when Gray announced, "The jury finds Thomas Cullen Davis not guilty."

Davis then stood and addressed the jury. "Thank you, ladies and gentlemen.

I want to thank you all," he said, and then hugged his tearful wife, Karen, who appeared in the courtrooms throughout the 15-week trial.

Several hours later, the Tarrant County district attorney's office dropped five pending criminal charges against Davis growing out of the murder-for-hire plot and a 1976 shooting spree at the defendant's $6 million Fort Worth mansion.

An Amarillo jury in 1977 acquitted Davis on a charge that he murdered his stepdaughter, Andrea Wilborn, 12, in the Aug. 2, 1976, shooting that left two people dead and two others wounded. Although never convicted of a crime, Davis has spent 612 days in jail since his 1976 arrest.

A mistrial was declared in Davis' first trial, on a charge that he solicited the murder of the first presiding judge in his protracted divorce case, when a Houston jury in January deadlocked.

Prosecutors argued that Davis plotted the death of Judge Joe H. Eidson Jr. in retaliation for more than 15 adverse rulings the judge handed down in the four years he presided over Davis' divorce case, long a media sensation in Texas.

The Fort Worth industrialist claimed that he was the victim of complex conspiracy concocted by his ex-wife, Priscilla Davis, the state's star witness, Charles David McCrory, and others.

The key prosecution evidence was a series of audio and audio-video tape recordings in which Davis and McCrory discussed a murder-for-hire scheme.

"I got Judge Eidson dead for you," McCrory told Davis in a taped conversation on Aug. 20, 1978, just minutes before Davis' arrest.

"Good," Davis responded.

McCrory said, "I'll get the rest of them dead for you. You want a bunch of people dead, right?"

Davis said, "All right."

The videotape made by FBI agents hidden in a van, purportedly shows Davis surrendering an envelope containing $25,000 earmarked for a nonexistent hit man, while accepting from McCrory a silencer-equipped pistol he had requested.

"Goddam pretty," Davis said, when shown the silencer.

McCrory testified that he showed Davis an envelope containing a staged photograph of Eidson's body crumpled in the truck of a car and identification cards belonging to the judge.

Davis contended that he never intended to have anyone killed, and agreed to participate with McCory in the tape-recorded discussions of mass murder only after receiving telephone instuctions from a man who identified himself as FBI agent Jim Acree.

Davis had testified that the man he believed was Acree telephoned on Aug. 10 and told him McCrory was involved in an extortion plot against Davis. From the witness stand Davis said he agreed to play along with McCrory, and discussed mass murder in a taped meeting the next day, but that he later learned the caller was not Acree.

Chief prosecutor Jack Strickland was smiling before today's verdict was announced, but his face soon turned ashen.

"I thought we might have a mistrial here, but I certainly never expected a not-guilty verdict. This is the worst I ever expected.

"I don't know if it is possible to convict Cullen Davis. It makes me wonder whether there is a dual standard."

A beaming Haynes attributed the jury's decision to the shorter and more precise case he presented in the Fort Worth retrial.

"I think we had a jury on balance there (Houston) that was a less intelligent jury. They didn't have the intellectual wherewithal to withstand prosecutorial rhetoric," the flamboyant Houston lawyer said.

The jury concluded that the tape-recorded discussions corroborated Davis' testimony. "We went over everything thoroughly," said the jury's foreman, Robert White Jr. of Arlington, Tex. "We had made up our minds after we had gotten to listen to the tape testimony."