Who killed who?

This is a little short I wrote, at the time I was contemplating a Iraq or Afghan vet who accidentally kills his parents during a blackout caused by a careless fire cracker.

***

Sam called at seven in the evening as he had said on the note Lionel found under his windshield wiper. Sam asked him to bring Danny and meet him under “the overpass”, a worn out and rarely used bridge the three had played under and later used as a refuge from their perspective world. Lionel agreed and hung up, he opened a drawer next to his bed and removed a 9mm pistol and tucked into the rear of his pants. He called for Danny and told him of the situation. They both headed to Lionel's car and headed off, driving almost ten miles before Lionel broke the uncomfortable silence.
“Do you think we’ll be able to convince him to turn himself in?” Lionel asked
“If not then we just call the cops but it will look better if he turns himself in.” Danny replied
“There is no way he did it. Sam just isn’t a killer. He loved his parents.”Lionel said shaking his head as if trying to magically understand the insanity of the afternoon.
“I know but the neighbors heard gunshots and saw him tear off in his car. It’s doesn’t look good. There has to be an explanation, His parents were great to him, he had a perfect model of the perfect family. Sam would never hurt them, or anyone for that matter.” Danny replied, as if he were still clinging to the hope that Sam was innocent even though in his heart he knew his old friend had changed.
Lionel turned onto the isolated road leading back to seemingly nothing but an old bridge from a road no longer used. They saw nothing on the slow mile or so trip back to the bridge. As they pulled up Lionel pulled out his pistol and chambered a round before ensuring the safety was on and tucking it back into his belt line.
“Jesus Lionel, what the fuck is that for?” Danny asked with a look of disbelief on his face.
Lionel placed his hands hon the steering wheel, let his eyes close and head bow before releasing a deep breath that seemed to go on for minutes.
“Listen Danny, Sam has changed, something happened to him over there, I just want to ba careful dealing with him. I don't want to believe he did it any more than you do but still have consider the possability that he did it.” Lionel said without moving or altering himself.
“You really think he would hurt us?” Danny said with mick contempt, not really needing a response.
“I am only saying that if he killed his parents then what is to stop him from trying to hurt us if he doesn't like what we have to say? We have to consider that.”
“I know.” was Danny's simple reply. He did know.
Sam was in a state of remorseful panic“Danny I am so sorry. Can you ever forgive me? I didn’t mean to. It just happened.”
Danny “You mean you did it?!?!?”.Danny yelled in a mix of disappointment and confirmation.
“I couldn’t help it Danny, Fluffy started sniffing my nuts and one thing led to another after that and…Oh God Danny I didn’t mean to. I am so sorry.”
“What?” Danny replied, confused.
“Why Sam. Why’d you do it?” asked Lionel, his voice breaking, his eyes tearing up.
“I don't know, one moment Dad was telling me about how he lined a job up in the shop for me, then I heard a bang and blacked out, when I came to they were dead. Oh my god guys, my mom and dad, I love them so much....” Sam became unintelligible as he drifted off into sobs.