Transcript for The tragic murder of Rebecca Schaeffer
Next to new reporting about a stalking tragedy that stunned America and led to new laws in the country. Actress Rebecca Schafer was filled in her front now. And now a new interview with co-star about what happened. Here is Matt Gutman. Reporter: She was the fresh-faced girl next door who skyrocketed to fame on the hit show "My sister Sam" in the 1980s. Life isn't this good. I must be dreaming. Reporter: Rebecca Schaeffer, the down-to-earth Hollywood star who answered her own fan mail. I went, "Wait a minute. You're answering them back? You can't do that." And she says, "Oh, no, but I love it and they want to be friends." And I went, "Wait, they're not your friends." Reporter: One of those fans Robert Bardo, a mentally ill young man from Arizona. Bardo grew obsessed, showing up at her studio, then becoming enraged when he saw Schaeffer acting in a love scene. It was the stalking case that turned deadly and sparked new laws in the U.S. All those rageful feelings. "How dare she?" That gets converted into a plan of cold-blooded revenge. Reporter: One day, 21-year-old Schaeffer was expecting a knock on the door. The script for "Godfather part III." Instead it Robert Bardo waiting at her door. He hired a private investigator in California to go to the DMV and find out where she lived. Reporter: The young actress tried sending Bardo away but he came back and shot her dead. And they would just hand him her address? I was ballistic with rage. Reporter: Bardo was sentenced to life in prison and now in a new interview, saying to and he feels the guilt. I realize what I've done and I feel a lot of tremendous guilt. Reporter: Schffer's family doesn't care what he has to say now but they're grateful their daughter's death prompted change. Later, a new tool, social media, makes it easier for stalkers to track their victims. While the laws got better, stalking has not diminished. In fact, it's on the rise. Reporter: To combat it, David, the DMV is now prohibited from giving out personal information and police depts across the country like the LAPD now have anti-stalking task David? The new edition of "20/20" is at 9:00 P.M. Right here. There is more ahead on this the deadly accident at a water park.
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