The Case involving Ashton Lundeby's home computer

[D-cat]

and I'd argue that a MAC address can be spoofed easier than an IP address. Your MAC (Media Access Control) number that's engrained in the hardware is only a default that can be easily overridden; your MAC is only what it is because your computer says it is. If someone is good with their network tools (especially Linux based), they can easily match their MAC with the one with the address their stealing. This is actually almost more sinister, since on the same ISP local net, the ISP will likely also issue you the same IP as the person your stealing, since the same MAC would have recently requested it. Aside from a few potential routing issues (which may go unnoticed on the same cable, if the perp is a neighbor as claimed), the spoof is a complete ghost on the network, stealing access masked as another user.

This is the exact reason those definable MAC cable modems we were discussing over a month ago are so hard to find now: their intended use is usually illegal, and this is the kind of thing you can do with them.

Edit: @DaWoo - As the law may be relevant to this discussion, here's the link you attempted to provide for us. Thank you.
18 U.S.C. § 2511 Interception and disclosure of wire, oral, or electronic communications prohibited

[DaWoo]

D-cat ... I can not disagree at all!! And thanks for posting the link.
And I know all about the "definable" MAC cable modems. Truth is anyone with the desire and ability to spoof MACs and IPs are pretty dangerous. But most are not good enough to cover their tracks.