I've been reading sci-fi novels for quiet a while, so I might have a few ideas. I know you said suicide, but could the death have been accidental?
But if the brother commited suicide, he was likely depressed, and in a futuristic world there might be depression counter-measures such as head implants that give off a low voltage electrical current when they sense signs of depression. The current would either interact with certain nerves, which would then send non-depressed signals to the brain, or to be a little blunter, the current would simply numb the brain and give a good feeling like drugs.
For a suicide, the brother could have modified the implants to give off a higher voltage, deadly, electrical current the next time he became depressed, therefore killing him.
I didn't want to elaborate too much, its your story, sorry :P

Cool idea zutial, (btw, Hi. I haven't met you before...) But then how could the nephew be implicated? Maybe...he's a techno-whiz? And could have possibly hacked into his uncle's thing? Oh-oh-oh! Or maybe the uncle modified his thing from the nephew's computer, using his account!
Er..sorry Trav. Are we overboard?

(Greetings to zutial)

I think these are good ideas Trav. Or maybe the uncle shot himself (or whatever- a fatel 'blow') and the nephew comes up to him as he is dying. Th uncle shoves the weapon into the good guys hand and dies. The nephew is so shocked that he doesnt know what to do. Later when someone else comes in -someone who doesnt know the good guy and doesnt know that he would never do such a thing- he sees the guy with the weapon and the nephew is convicted. Its not very original and might be cliche but thats my idea,

At the moment, I'm kind of liking Zutial and Pars' ideas. I'll have to think on this one...

THats fine

So how has it been working for ya?

Decent! I actually like where it's going, and my chars are cooperating nicely. Thanks for the ideas, Zutial. And Pars.

Pay no attention to the bird behind the curtain!!
Trav is a SHE
http://www.musings-in-a-strange-land.blogspot.com/
I am a Wraith of Yore...fear me and my power of forgotten-thread blackmail

Now that you have us all curious... Will you post it when its done?

Maybe...but I'm thinking it will be pretty long. I'll prolly post it on ApricotPie, though.