While every case is different, the general rule is that it is favorable to secure legal representation as early as possible in a criminal matter. It is also favorable to begin a pre-file investigation as early in a case as possible. This is for the following reasons: Events are still fresh in people's minds; Witnesses are more likely to be available to interview and question; and, It's likely that evidence has not been tampered with, which is a crime per California Penal Code 141.