Warranted: arrest warrants

Last week we discussed the general requirements for obtaining a warrant. This week we’re getting more specific—we’re talking about arrest warrants.

Just to review, an arrest is a type of seizure, and therefore the requirements of the 4th Amendment apply. But even though that amendment implies you need a warrant, a long series of cases says not so much. In fact, police never need a warrant to make an arrest if the person is suspected of a felony. They also don’t need a warrant to arrest someone who’s committed a misdemeanor in their presence. So the only time they must have a warrant is for misdemeanors that the police didn’t witness. This constitutes a pretty small proportion of arrests, so in practice, arrest warrants are rarely required.

However, even if police don’t have to get a warrant prior to making an arrest, they might choose to do so. Why? Well, a warrant offers some potential benefits:

  1. It gets the suspect’s name into the system. This way, if the suspect is later stopped for something else—perhaps something small—police can easily tell whether he’s wanted for another crime. One of my students once failed to pay a speeding ticket or appear in court, so a warrant for failure to appear was issued in his name. Later he and a buddy decided to go swimming in an apartment pool after hours. Someone complained, cops came, and when they checked Steve’s name, there he was. He ended up spending the 4th of July weekend in the local jail.
  2. With an arrest warrant, the police can enter any property where the suspect is, without getting a search warrant. Absent an arrest warrant or search warrant, police can’t enter private property unless they are in hot pursuit of a fleeing felon (that is, the crime has just occurred) or some other emergency exists.
  3. Before getting an arrest warrant, a cop has to convince a magistrate or judge that there’s probable cause that the suspect committed a crime. This provides somewhat of a guarantee that the arrest won’t later be thrown out (by a judge) for insufficient evidence.

Even when a warrantless arrest is made, police must still have probable cause. An arrest made with less than probable cause is illegal and will be invalidated, ending the case.

Incidentally, want a plot bunny? Alma invites her friend Brad over to her house, unaware that Brad has an active arrest warrant out in his name. The cops see Brad enter her house and barge right on in after him. Too bad for Brad. But also too bad for Alma, who’s been packaging heroin in her living room. When the cops see the drugs, they arrest her too.