Demystifying Criminal Law: The Criminal Investigation, Arrest & Arraignment

Posted March 9, 2010 in Demystifying the Law by

I have a confession to make. I’ve worked in the legal profession for years (as a non-lawyer), but a lot of what I first learned about the criminal justice system came from shows like "CSI" and "Law & Order," and books by authors such as Scott Turow and John Grisham. You’re probably no different from me, unless you’ve personally been affected by crime.

At, we want to help people better understand the law. To that end, this is the second of three blogs in which I’m trying to demystify the criminal justice system. Last Thursday, I focused on Who’s Who in Criminal Law. Today we’ll look at the criminal investigation process, arrests and arraignments. On Thursday, we’ll focus on criminal trials.

It’s important to mention that the criminal justice process does vary from jurisdiction to jurisdiction. In general, the process involves the following stages:

  • Investigation
  • Arrest
  • Charges
  • Arraignment
  • Bail

Investigation, Search Warrant & Interrogation

Once the police learn of a crime, they will launch an investigation. During the investigation, the police are gathering evidence to help them determine what crime occurred, who committed the crime, who was the crime victim and how the crime the crime was committed.

If investigating officers believe there’s evidence of a crime at a particular location, they may try to get a search warrant, which allows them to search the premises. A judge will review the information submitted by the police and decide whether there are enough facts to support the belief a crime occurred at the location described in the warrant.

During the investigation, law enforcement can interrogate witnesses and question potential suspects.


If police believe that there’s probable cause to believe that a specific person committed a crime, they may arrest the person under suspicion and take them into custody. Police can also arrest a person who commits a felony or misdemeanor crime in their presence. Finally, police can arrest a person if they think the person committed a felony even if the police office didn’t witness the crime.

An arrest may be made in a public place, with or without a warrant. But if law enforcement officers want to arrest someone in a private place, the police have to first obtain an arrest warrant. (There are certain circumstances where an arrest warrant isn’t necessary.)

Law enforcement officials have a relatively short period of time following an arrest (usually with 24 or 48 hours, depending on the state) during which they must either charge the person with a crime or release them.

Charging a Suspect

Before or after a suspect is arrested, law enforcement officials need to decide whether to charge the person with a crime. These written charges are called a complaint or an information. Once charges have been filed, police can keep a suspect in custody until the next stage in the criminal process.

Arraignment & Bail

An arraignment (sometimes known as a preliminary hearing) is the formal presentation of charges in court. During the arraignment, the judge reads the charges to the accused person (now known as the defendant), and asks the defendant to plead guilty or not guilty to the charges.

The defendant’s lawyer may be present, or an attorney appointed by the court may represent the defendant.

The judge may allow the defendant to be released until his or her trial date, or may require the defendant to remain in custody. There is no guaranteed right to be released on bail. If a judge believes that a defendant may flee or fail to appear for future court dates, or if the defendant is charged with a serious crime, then bail may be denied or cost so much that a defendant may not realistically be able to post bail.

In much less serious offenses, an individual may be released on relatively low bail. If the defendant is released without bail, this is sometimes referred to as being released into one’s own recognizance, or "R.O.R."

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