Embattled actor Stephen Collins fears his past sexual misconduct with underage girls stemmed from his own childhood trauma with an older woman.

During his first official Tv interview since the scandal broke earlier this year (14), the 7th Heaven star told U.S. newswoman Katie Couric his early sex encounters may have helped him justify his actions with girls as young as 10.

In the news special, which aired as part of 20/20 on Friday night (19Dec14), Collins said, "I did have someone in my life when I was between the ages of about 10 and 15, an older woman, who repeatedly exposed herself to me, and I think that distorted my perception in such a way that some part of me thought... I got the equation of, 'Well, this isn’t so terrible. This person who I trust is doing it'.

"There was a power that she had over me that was intense... It’s also about a very distorted form of approval."

The 67 year old has admitted to behaving inappropriately with children between 1973 and 1994, but told Couric he never sought sexual gratification from his victims and is not attracted to young girls.

He revealed, "In 1973 there were two occasions when I exposed myself to this young woman and several months later she came to visit and stay with my first wife and me. My wife had gone to sleep and she and I were watching Tv alone together and I took her hand and moved it in such a way that she was touching me inappropriately. Neither of us moved.

"I knew immediately at that moment, I knew that something unthinkably wrong had just happened that I couldn’t take back and I think we both just sat there. We really didn’t move a muscle and after about 45 seconds I took her hand and moved it back.

"I waited a couple minutes because I didn't know what to do or say and then I got up and left the room and I never had any physical contact with her of any inappropriate kind after that. That was the only physical contact I have ever actually had with any minor."

Collins' inappropriate actions came to light earlier this year (14) when audio from a therapy session the actor attended with his wife leaked online.

In his Tv chat with Couric, he also confessed to exposing himself on two occasions to a 13-year-old and a 14-year-old girl, adding, "I did not know either of them really well but they were not strangers."

And he told the newswoman he has not engaged in inappropriate sexual behaviour post-1994, two years before he was cast as Tv preacher Reverend Eric Camden in 7th Heaven.