Now, 30 years on from the deadly stand-off, the mum of four has controversially insisted that she still believes in the teachings of the charismatic preacher, who claimed he was the second coming of Christ.
In a new Netflix documentary, Waco: American Apocalypse, the cult’s survivors and agents involved in the 51-day siege at a remote Texan ranch recall the horrifying events which ended in an enormous fireball on April 19, 1993.
And Kathy makes a twisted defence of child sex abuse by Koresh, who took a 14-year-old as one of his many wives and was accused of having sex with girls as young as ten.
Kathy, now 60, says: “People think that a man having sex with a lot of underage girls is a crime and in conventional wisdom that could probably very well be true.
“However, these weren’t underage girls, because you come of age at 12. So all these girls were adults in our belief system.”
Three decades after he brainwashed her, Kathy still defends Koresh’s abuse of women.
She says: “Every single one of us was married to David because David was our Christ giving us the truths from God. The whole time we were having sex it was a bible study.
“He did it to give me that one little bit of tenderness with my God.”
The documentary features never- before-seen footage from the chaotic siege, which began with a shootout between the cult and federal agents.
‘Talking to God’
Former FBI officers reveal how the escalating power struggle between negotiators and gung-ho enforcers led to the final fireball that killed Koresh along with most of the victims.
Koresh convinced his followers the end of the world was coming and they should be armed for “war.”
He amassed a huge armoury of over 50 illegal machine guns, 1.5 million rounds of ammunition and 1,000 grenades — sparking federal agents’ initial raid on the house in the Mount Carmel Center on February 19, 1993.
FBI hostage negotiator Gary Noesner says his organisation’s strong-arm tactics during the ensuing stand-off led to many lost lives.
He says: “We did not save every life we could. Therefore in my mind, it’s a failure.”
David Koresh — real name Vernon Wayne Howell — had a nervous breakdown in 1979, when, according to ex-girlfriend Linda Campion, “he thought he was talking to God.”
In his early twenties, he joined the ultra-religious Branch Davidians and took it over in 1989, introducing his twisted doctrine, the New Light.
He claimed God wanted him to have 24 children, who would be chosen as the ruling elders after the second coming, and ordered him to take 12 wives, one of whom was 14-year-old Michelle Jones, younger sister of legal wife, Rachel.
He also “dissolved” the marriages in the Waco community and decreed only he could have sex with women there.
Heather Jones, whose parents were raised in the sect, was nine at the time of the siege and says that before David seized power it was a “caring environment”.
But she says the New Light decree split her family, adding: “My dad went along with it, my mum didn’t agree with it, so in the middle of the night she packed up and left.
“After she left I wasn’t allowed to be around my dad. David Koresh was my mum and my dad.”
Although she was never sexually abused by Koresh, she details horrific physical abuse.
Now 39, he says: “The girls who were between ten and 13 would giggle and laugh about being one of his wives one day, having his kids, how much it was an honour.
“But not me. He was hard on me for everything. Down to the spankings, with a really big paddle.
“He would take me in his room, and make me lay over his lap. That happened almost every day. A lot of people have told me he was grooming me.”
Like all the children in the commune, Heather and her two brothers were taught to fire guns.
As well as stockpiling explosives Koresh was converting semi-automatic assault rifles into illegal machine guns, and even had a 50-calibre Barrett rifle which could penetrate armoured vehicles.
The huge arsenal came to the attention of the US government’s Bureau of Alcohol, Tobacco, Firearms and Explosives, which planned a surprise raid on the property.
But a news photographer, who had been tipped off and got lost on the way to the ranch, asked a passing mailman for directions and let it slip that agents were moving in.
That mailman was David Jones — Heather’s dad.
He reported straight back to Koresh, who told followers: “The time has come.”
As helicopters flew overhead, and 50 armed agents spilled out of two cattle trucks, the biggest gun battle on US soil since the Civil War broke out.
Heather saw bullets flying through the windows and witnessed one of Koresh’s wives, who was armed, being shot dead.
‘Upset and angry’
She also heard her grandfather Perry, who had been shot in the stomach, screaming and begging to be killed.
He was allegedly “put out of his misery” by his fellow cult members.
Four law enforcement officers died in the battle.
After withdrawing from fire, agents managed to contact Koresh — who had been shot — and negotiate a ceasefire.
In chilling recordings, Koresh can be heard telling the ATF handler: “There’s a bunch of us dead. There’s a bunch of you guys dead. Now, that’s your fault. You got your big butt whooped.”
Over the next 51 days, FBI negotiator Gary Noesner and his team built up a rapport with Koresh and eventually persuaded him to release the children “two by two” in return for his messages being broadcast on a religious radio station.
Koresh kept his 14 biological children in the house with him because they were “chosen ones”.
But Kathy’s four children — Scott, Jake, Crissy from her first marriage and three-year-old Bryan — were among the 19 who left, along with Heather.
Kathy’s older children were taken by their father, who was not a cult member, but little Bryan was left alone in a children’s home.
The FBI used video footage of him, looking alone and forlorn, to lure Kathy out of the compound.
But just minutes after her tearful reunion with Bryan, Kathy was arrested and carted off to jail.
She was eventually sentenced for three years for attempted murder, after striking a bargain for a lesser sentence for testifying against 11 surviving cult members.
Negotiator Noesner was “upset and angry” at the trick because Koresh’s followers would know what had happened and would be less likely to surrender.
The Hostage Rescue Team, under pressure to end the siege which was costing over £800,000 a week, began a fresh assault the day after Noesner negotiated the exit of seven more members.
FBI boss Jeff Jamar sent in tanks to crush the group’s cars just as Noesner felt there was a chance the stand-off could end peacefully.
In a recording, Koresh is heard telling him: “We had an agreement and it was working out. Your side destroyed it.”
The HRT tried in vain to get the group to surrender by blasting out recordings of jet planes, pop music, Buddhist chanting, and screams of rabbits being slaughtered.
Finally, after getting the all clear from US Attorney General Janet Reno, the FBI began punching holes in the wall using explosives and firing tear gas grenades into the building.
On April 19, three fires were seen burning on different parts of the building.
There is dispute over whether they were set by the FBI or cult members.
Koresh and all the remaining members left inside were killed.
Bob Ricks, the special agent in charge of the operation, believes Koresh played the FBI all along.
He said: “We had to respond to the demands of David Koresh and we were like actors in his play.”
Still under Koresh’s spell, Kathy points out he was 33 when he died — like Christ.
And she still believes the message of salvation for his followers rings true.
She says: “Watching everybody I know die is painful but acceptable because they did it for a reason.
“They did it for their own glory, worship and praise of their God.”