Many people understandably wait until they’ve been charged with crimes to get legal representation. After all, arrests don’t automatically result in prosecution—in most cases, the local prosecuting office (often called the district attorney’s office) decides whether to file charges after arrest. Some people who’ve been arrested never need lawyers because they never face charges. (That said, people in this situation may want to seek legal guidance about, for example, getting a conviction expunged or clearing a record of arrest—see Expungement or Sealing of Adult Criminal Records.)
There’s often not too much a lawyer can do before the filing of charges. But, depending on the investigating police officer or decision-making prosecutor, attorneys can sometimes—albeit rarely—stop cases in their tracks. For instance, sometime relatively soon after a client’s arrest, a lawyer who believes the client’s version of events might call the prosecutor responsible for deciding whether to file charges. If the prosecutor is willing to talk and provides information that happens to be consistent with the client’s story, the defense attorney might give persuasion a shot: Every once in a while, lawyers are able to talk DAs out of filing charges, or into filing less serious charges.
Even before that point, a lawyer might get in touch with the investigating officer and try to dissuade him or her from passing the case to the district attorney’s office with the recommendation to file charges. (Of course, police officers often aren’t interested in talking with lawyers unless they think they can get an interview with the client—see Should I meet with the prosecution or police about my case?)
Ultimately, it may be impossible to talk the police or prosecution out of pressing on with a case before it even gets started. Oftentimes defendants don’t even have the opportunity to speak with lawyers before their first court appearances, by which time the prosecution has already filed charges. But for those who’ve been arrested and are waiting to see whether and what the prosecution will file, talking to an experienced criminal defense attorney often makes sense.