Lloyd Blankfein, chief executive officer of Goldman Sachs (NYSE:GS), has hired high-profile criminal defense lawyer Reid Weingarten.

This is a game changer even if we don’t yet know where the fire is.

Blankfein has led the firm for six years and spent the past two dealing with allegations of conflicts of interest and fraud. A Senate report released in April said Goldman dumped subprime loan exposure onto unsuspecting clients during the mortgage meltdown, then in 2010 gave Congress misleading testimonials about the firm’s actions.

So far, Blankfein has not been accused of any crime or crimes. That means, and I cannot stress this strongly enough, that he is innocent in the court of law — even if he is held slightly above pond scum in the court of public opinion for his and Goldman’s role in causing the financial crisis.

Under the circumstances, I cannot help but wonder:

Is the U.S. government’s investigation into Goldman Sachs (and other financial houses) gaining momentum, and has the government notified Blankfein that he is a person of interest in one or more of those cases?

Is there a whistleblower inside Goldman, or are there key players who have “rolled over” in an attempt to protect themselves?

Is Blankfein retaining Weingarten personally on his nickel? If so, at whose direction? (I also can’t help but wonder if Goldman’s interests and those of its senior executives have separated as a result of the increased legal scrutiny …)

Could Blankfein have some sense of what’s in the wind and simply be making a preemptive grab to obtain the best counsel before others who also will need criminal counsel do the same thing?

Or is there something as simple as a conflict of interest that has yet to emerge publicly?

At this point there are more questions than answers … but I have a feeling this won’t remain the case for long.

Allegations against Goldman of trading against its clients and favoring certain clients over others will not fade quietly into the night this time around, with the global financial crisis having wiped a whopping $28 trillion from global markets in 2008.

The news of Blankfein’s hire pushed down Goldman shares 4.7% late Monday to close at $106.51.