River's Edge

The movie opens with a boy, Tim (Joshua Miller) playing on a bridge. He hears a yell, and sees Samson/John (Daniel Roebuck) sitting on the shore. The boy pedals off, and Samson smokes a cigarette by the naked corpse of Jamie (Danyi Deats). Samson leaves in a daze, and Tim spots him at a convenience store. While Samson haggles with the clerk, he steals two beers and leaves them for Samson. Tim asks Samson for dope, and gets in Samson's car. They drive to Feck's place for drugs, but he's not home.As Tim returns home, his brother Matt (Keanu Reeves) is arguing with his mother (Constance Forslund). His little sister Kim (Tammy Smith) wants Matt's help for a funeral for her lost doll, and we learn that the family is dysfunctional. Layne (Crispin Glover) arrives to pick up Matt, and Tim asks to come along. Layne refuses, and Tim bicycles off, despite his mother's complaint. Layne and Matt arrive at Feck's house, where Feck (Dennis Hopper) is playing saxophone for an inflatable doll. Layne gets drugs from Feck, and Feck talks about the girl he had to kill.At school, Layne and Matt smoke pot with Clarissa (Ione Skye) Maggie (Roxana Zal) and Tony (Josh Richman). Samson/John arrives and takes them to see Jamie's body. Matt is nervous and leaves, and Layne starts planning how to get alibis.Mr. Burkewaite teaches his class about radicals, and Clarissa flirts with him. The murder story starts to spread, and Layne tries to borrow Mike's (Phillip Brock) truck. Mike refuses, but is willing to drive. They see the body, and Layne tells them to help bury her. No one is willing to help, including John. Clarissa is uncomfortable with the secret, but Layne threatens her. She's too scared to call the police, and later calls Matt, but Matt is too shy to talk.That nigth, Layne rolls Jamie's body into the river. John buys him beer, but doesn't seem to care that Layne is trying to protect him. At John's house, they see police cars. Layne panics, but John is calm. They go to Feck for help, and Layne leaves John with him. Feck recognizes a kindred spirit, and they begin to talk.Matt brings detective Bennett (Tom Bower) to the place where the body was, and the cops fish her out of the river. Bennett grills Matt about the murder. Matt's mother picks him up from the police station, and he gets in a fight with her boyfriend Jim (Leo Ross). Tim appears, and Matt chases him. Tim threatens Matt with telling Layne about Clarissa's phone call, and Matt hits him. Tim runs off, and meets up with his friend Moko (Yuzo Nishihara). They borrow his father's car and head to Feck's.Layne, Clarissa and Matt go to Mike's house to extract his confession, but Mike's father drives them off with a shotgun. Layne gets annoyed and kicks Clarissa out of his car. Matt gets out and walks her home. She kisses Matt and they decide to go to the park. On the way, they stop at the convenience store and bump into John and Feck, buying beer.Layne arrives at Feck's, and Tim/Moko hide. After Layne leaves, Tim and Moko enter and search for Feck's gun, but find weed instead. They get wasted at Feck's.Meanwhile, John and Feck break into a store and steal ammo. Matt confesses to Clarissa that he told the cops about Jamie. They begin to make out. John and Feck wind up at the river's edge, and John starts messing with Feck's doll. Feck realizes John is crazy, and tries to calm him down. John starts firing Feck's gun, and brags about his murder.Matt hears the gunshots, but doesn't stop making love to Clarissa. They fall asleep in the park.Layne is cruising around, looking for John and popping pills. Feck muses about getting old, then fires a shot. When he comes home, Tim and Moko attack him and take his gun.In the morning, the police find Layne, passed out in his car, and take him to the station for questioning. Matt returns home, and his mother screams that she's leaving her kids.Reporters interview kids at the school, and Bennett questions Layne. In class, Burkewaite rails about morality, and that no one cares about Jamie. Clarissa is distraught. Tim watches Matt and Clarissa, holding Feck's gun. Layne calls Feck, and the police break in on Feck, so Layne hangs up.The kids go to the river's edge to skip school, and Matt sees Feck's doll in the river. Layne arrives and tries to attack Mike again. Matt intervenes and tells Layne that he turned John in. Layne runs off, then finds John, dead. Tim shows up and tries to shoot Matt for hitting him, but Matt talks him out of it. The police arrive and cart everyone off.At the end, Feck is in the hospital, confessing to his original murder and for killing John. The movie ends with Jamie's funeral, and the kids finally show emotion.

Question: Who told the cops about the naked corpse?
Answer: Matt