That's not a technical problem though is it? I don't see legal scenarios where unverified machine translation is acceptable - you need to get a certified translator to sign off on any translations and I also don't see how changing that would be a good thing.
I think the point here is that, while such a translation wouldn't be admissible in court, many of us already used machine translation to read some legal agreement in a language we don't know.
I was briefly considering trying to become a professional translator, and I partly didn't pursue it because of the huge use of MT. I predict demand for human translators will continue to fall quickly unless there are some very high-profile incidents related to MT errors (and humans' liability for relying on them?). Correspondingly the supply of human translators may also fall as it appears like a less credible career option.