Fox was charged with the offence in May after being caught drink-driving in his hometown in Oregon, and later struck a deal to avoid jail which meant that he had to attend a treatment programme and stop driving for a year.
"I was not happy about the DUI at all," Fox said on The Ellen DeGeneres Show. "I was terribly embarrassed about that and take full responsibility for it.
"I mean, I really own that and have done every single thing that the state of Oregon requires for a first time DUI offender. I've learned a ton. I did four weeks of alcohol informational training and just learned an enormous amount."
Fox admitted that he was appalled to learn that 50% of people who get a DUI will reoffend, saying: "I found that pretty outstanding after what I've been through. I will absolutely not be in that statistic. There's just no way."
The former Lost star also confessed that he feels he should have known better after growing up in Wyoming, where he had to drive 60 miles to go to town.
"From a very early age, that's just what we did, and I lost friends in high school that were drinking and driving and had accidents on the highway," he said. "So I should have known better, and yet I did that off and on throughout my life. Fortunately [I] didn't hurt anybody and then learned this lesson, so it'll never happen again."
Fox also used his appearance on Ellen to put across his side of the story about the assault case filed against him last year, which was ultimately dropped.
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