What Happens If a Lawyer's Doesn't Know All the Facts Concerning the Case ?
There are certain minimum standards that counsel must meet, however In Ex parte Welborn, 785 S.W.2d 391 (Tex. Cr. App. 1990), the court explained that:
It is evident that a criminal defense lawyer must have a firm command of the facts of the case as well as governing law before he can render reasonably effective assistance of counsel. Ex Parte Ybarra, 629 S.W.2d 943, 946 (Tex.Cr.App. 1982); Ex Parte Duffy, 607 S.W.2d 507, 516 (Tex.Cr.App. 1980).
A natural consequence of this notion is that counsel has the responsibility to seek out and interview potential witnesses. Ex Parte Duffy, 607 S.W.2d at 517.
It may not be argued that a given course of conduct was within the realm of trial strategy unless and until the trial attorney has conducted the necessary legal and factual investigation which would enable him to make an informed rational decision. 607 S.W.2d at 526.
Counsel has a duty to bring to bear such skill and knowledge as will render the trial a "reliable adversarial testing process." 466 U.S. at 688, 104 S. Ct. at 2065, 80 L. Ed. 2d at 694.
In other words the presumption of reasonable trial strategy does not attach unless and until counsel has conducted the necessary factual and legal investigation.