Anyone who feels their coins have been unfairly locked, because they weren't part of the Mt. Gox wallets, can just provide proof of ownership to the appropriate group to have the addresses removed from the locked list. Clearly this would require good evidence, but that can be arranged and weighed appropriately.
What "appropriate group"? The central bank of Bitcoin? The Central Bitcoin Intelligence Agency?
You have no idea which addresses belong to MtGox. It doesn't strike you as utter contemptible to just start blocking addresses because you think they belong to MtGox? Forget laws, on what ethical or moral authority do you have the right to arrest the wealth on another person?
There is nothing wrong with the Bitcoin community, as a consensus, saying they want to be just and support law enforcement in such cases. In fact, I would argue it is using available information and the capabilities of new crypto-currencies in a freedom supporting way.
Except by the responses of this very thread you already don't have a consensus and that is with only a tiny number of people knowing about it. What you want is a central all powerful authority to control the wealth of others based on the flimsiest of evidence. Evidence which BTW wouldn't be sufficient in a court of law to freeze assets
"Your honor we think these assets might belong to the defandant so we want you to freeze them for an indefinite amount of time just in case. This was thoroughly researched by some people on the internet and stuff.".