Can police trace your ip address even if you use a proxy?

[Luke]

I play this game called warcraft 3 and this guy I played with used a Denial of Service (DoS) attack on my computer and shut off my internet, he's done it multiple times and he also uses a proxy, I know that using a DoS is illegal so I was wondering if I contacted the authorities they would be able to do anything or if there was some way to defend against a DoS attack

[Edmond]

Edit: Misread it. The answer for Warcraft 3 is maybe, as I am no longer familiar how WC3 does their account record/history for online multiplayer. They can still be caught, especially if they slipped up and supplied their actual email address which they verified which can be traced back to them, or said the incriminating message while not proxy-ing.

I also recommend contacting both your ISP and activision-blizzard about this as their property/service/good name regarding said service is being tarnished.

=== Ignore Below as I misread as WoW ===
Correct me if I'm wrong, but WoW still requires monthly monetary transactions to keep an account active for use. If you have the user/character name of the DOS-er and high suspicion of said user being behind the act (ie: said user boasting about the DOS, which I believe WoW servers record chat), then you should be able to trace it back to the DOS-er (or at least, the payer of the account).

If the suspect supplies info that only the DOS-er would know on a public chat (like WoW server) which has personal info, then they are boned. They might be able to fake a IP, but you can't fake an active credit card/transactions as easily.

[Krowten Nimda]

If you get the proxie's Address the police can request the logs from the server to see who was using at the times of the attack. Its probably not definitive, but it can help. Edmonds answer would have more luck, supposing the guy gave his actual information in the account.

[M]

Could they, probably. Would they, not likely. Especially if the guy is at all sophisticated and knows what he's doing. The cost to track this down isn't worth their time. Simply put, they are not going to care.

[Aafreen]

When i suggest utilizing http://www.vpnpower.net to be able to unblock sites. I have been with them since 5 years.