And now, a cigarette Horatio found at the cemetery gets stripped for a DNA sample while Calleigh looks over the baseball bat bag she found at the mausoleum. It's all very montage-a-riffic. When we get the results, the cigarette butt has three different donors, one of whom is Ben (they got his DNA from another cigarette sample). We also find out that the bat bag had been used to tote rifles.
Cut to Horatio talking to Nick the Neglectful Dad, bringing home the guilt by laying out photos of dead Mark and saying, "Your son is in a great deal of trouble." Nick immediately tries to pin it on the ex- and current-con's kid, pointing out that Ben's admitted he was shooting guns over at Jeff's. Ben is seated and looking, like, so embarrassed. Horatio asks if Ben mentioned anything about being at the cemetery the morning Mark Hubbard was killed. Nick's all, "He told me they go there in mornings before school for horseplay." Horatio talks to Ben: "I have a blood pattern, My friend, that says there were two people at the cemetery when Mark was shot to death. So, are you the shooter, or was Jeff?" Ben looks up all creepy-like and intones, "I'm not saying anything about Jeff." Horatio rolls with that and moves on to asking where the guns are. Nick's all, "What guns?" and Horatio explains, "They carried their rifles in a bag and foolishly left it behind." Heh. It's time some cop expressed contempt for how stupid criminals can be. Ben continues to not say anything, and Horatio leans down to put the fear of Caine in him: "I can wait."
Calleigh's found that the bat bag also had the Four Twenty Boyz written on it, which ties the bag to Jeff at the least, and probably Ben. Horatio takes his line of inquiry down the THC road, but Ben soon sets him straight: "It's not a time. It's a date. [April 20 is] Hitler's birthday. All around the world, the whole week." Horatio concludes, "So we have Waco, the Federal building, Columbine and now Antioch. So you guys were planning an action, weren't you?" Ben explains that he and Mark backed out; Jeff shot Mark, and threatened Ben to ensure his silence. Horatio asks where Jeff is, and Ben replies that he's at the mausoleum. Horatio calls him on that, and suggests, "Why don't you tell Me what time you're due out of school?" Ben says it's normally 3 PM, but there's an assembly today. Horatio quickly concludes that Jeff will begin shooting at 4:20 PM. I'm thinking that at that point in an assembly, some students might welcome the distraction.