In most criminal cases, the person who is charged will not end up being convicted on all of the original charges they faced. Often, cases will be resolved through plea bargains, in which the defendant agrees to plead guilty to a lesser charge or for dismissal of additional charges filed against them.
An overwhelming majority of criminal cases never go to trial, and they are instead ended with a plea agreement between the defendant and the prosecutor. Prosecutors often make such offers because they are simply unable to take every case charged to trial. Courts also do not have the time or resources available to conduct so many trials.
When criminal defense attorneys receivs a new case, they often investigate what happened as well as their client's history and circumstances. They do so in order to find mitigating evidence they can then use to advocate for a favorable plea or a dismissal if warranted. The factors that may have an impact include the person's criminal history, how the police conducted their investigation, the seriousness of the charges and whether important evidence is likely to be suppressed at trial. The defense attorney will then present various arguments to the prosecutor while negotiating to secure the most favorable outcome for their client.
When people are charged with a crime, they may face long sentences of incarceration and other severe penalties if they are convicted. Plea bargaining is one way in which criminal defense attorneys may be able to secure less severe consequences for their clients. Every defendant, however, has the right to determine whether or not they want to take their case to trial. They also have the ultimate say in whether they wish to accept a plea arrangement. While an attorney may provide advice, the ultimate decision rests with the client.