"A kid that suffers great trauma in their adolescence is much more susceptible to addiction disease later in life, especially if their parents had it.
"That's what happened to me. I come from alcoholism, I come from divorce, two of my uncles (John and Robert Kennedy) were brutally assassinated publicly. I was an angry, terrified kid at the age of 13 and drugs and alcohol gave me a way out.
"I was in the eighth grade, and when that thing (first drug) went into my system, all bets were off. What people don't understand is that if you have this thing, you can't just say 'no'."
He spent 17 years battling addiction, often hitting bottom.
"There was always this overwhelming dread of feeding the 800-pound gorilla. When can I go to the bar? When will I have enough? Will I get sick today? To live with that is hell, the first drink or first joint in the morning, just to get out of bed.
"I was going to follow my uncle Jack, JFK, my hero. I was to study history, win a Pulitzer Prize, become a war hero, overcome a major health problem and at 43, become President.
"But I moved in next door to a commune of heroin addicts, and that was the end of F. Scott Fitzgerald and Thomas Jefferson and hello to emergency rooms and doctors."
He still remembers vividly when his moment of clarity struck him.
"It was February 17, 1986. it was a freezing cold day in Boston. I was at the end. I had tried everything humanly possible - doctors, experimental drugs, drug therapy, changing girlfriends, going to graduate school, locking myself in a room for a week at a time to detox.
"That morning, I was done. I would have done anything. I thought I had to kill myself, because I couldn't get sober. I can't live like this. This is torture. But I didn't have a gun."
He called a cousin, who had recovered from addiction, who told him to go back to recovery groups.
"There's this magical ingredient for some people, and it's spiritual. It's attrition. If you have to knock on the door 500 times, you have to keep knocking until the door opens."
Mr Lawford eventually benefited after over 10 years of treatment, and said it was no-brainer to pour resources into treatment and prevention - even though there is no silver bullet.
"If you spend $1 on treatment, the benefit to society is $7 back. And you get $5 back from every dollar you spend on prevention. My message is that treatment works, and if we invest the money, we'll see the return."
He spent Monday at Arohata Prison, where he met a group of women with P addictions undergoing a six-month treatment programme.
"Many will relapse, but three or four of them won't, and they will no longer be a drain on society. They will become taxpayers and productive members of society."
He said addiction was often misunderstood, and it did not prevent him from functioning. He gained an arts degree from Tufts University, a doctorate from Boston College Law School and a Masters Certification in Clinical Psychology from Harvard Medical School - all while immersed in addiction.
"If you think all drug addicts are lying in the gutter, think again. They're mums, professors, lawyers, politicians. They're everywhere."
Now 56 and sober for 26 years, Mr Lawford still has to urge to escape - he just uses different methods.
"I drink caffeine like a banshee. I go to bikram yoga everyday, and when I'm in a cold place I have a hot bath and a cold shower just to shut my mind off.
"I have four kids who have never seen me drunk or stoned. I've been a father, an actor, I've made movies, written three (addiction-related) books, I'm a UN ambassador. I'm here, a productive, a useful member of society."
