What Does a Magistrate Do? Criminal and Civil Case Duties

A magistrate is a judicial officer who handles the procedural backbone of a case: signing search and arrest warrants, holding initial appearances, setting bail, running preliminary hearings, managing discovery fights in civil lawsuits, conducting settlement conferences, and trying smaller criminal and civil matters. If you’re asking what does a magistrate do, the short version is almost everything a court needs done before — and often instead of — a full trial in front of a district judge. The authority is narrower than a judge’s by design, and some of the bigger powers only switch on when the parties consent.

Criminal Case Duties

Signing Warrants

Before federal agents arrest someone or search a home, a magistrate judge almost always has to sign the warrant. Officers submit an affidavit laying out why they believe a crime occurred or that evidence will be found at a specific place, and the magistrate issues the warrant only if the affidavit establishes probable cause.¹ The Fourth Amendment requires that gatekeeping decision to come from a neutral decision-maker rather than from the officers running the investigation.²

Initial Appearance and Bail

After an arrest, the defendant’s first time in court is before a magistrate. The magistrate explains the charges, advises the defendant of the right to remain silent, and either appoints a public defender or confirms retained counsel. For felony charges, the magistrate also informs the defendant of the right to a preliminary hearing.¹

The magistrate then decides whether to release the defendant or hold them in custody pending trial. Federal law lists the factors: the nature of the charges, the weight of the evidence, the defendant’s ties to the community, and whether the person poses a flight risk or danger to others. Release conditions can run from an unsecured promise to appear, to a monetary bond, to electronic monitoring. In serious cases involving violence, drug trafficking, or significant flight risk, the government can ask the magistrate to order pretrial detention with no release at all.³

Preliminary Hearings

For felony charges, the magistrate conducts a preliminary hearing, essentially a mini-trial in which the government must show probable cause that a crime was committed and that the defendant committed it. The defendant can cross-examine witnesses and present evidence. If the magistrate finds probable cause, the case moves on to a grand jury or district court. If not, the magistrate dismisses the complaint and releases the defendant, though the government can still pursue charges later through a grand jury indictment.⁴

Timing matters. If the defendant is in custody, the preliminary hearing must happen within 14 days of the initial appearance. If the defendant was released, the deadline extends to 21 days. These deadlines can be pushed back with the defendant’s agreement, or without it if the magistrate finds extraordinary circumstances.⁴ Many preliminary hearings never happen in practice, because the government often obtains a grand jury indictment first and the hearing becomes unnecessary.

Misdemeanor Trials

For less serious criminal charges, a magistrate can handle the entire case start to finish. In petty offenses — Class B and C misdemeanors and infractions carrying six months or less of imprisonment — the magistrate conducts the trial and imposes the sentence without needing the defendant’s consent.⁵ For Class A misdemeanors, which carry up to one year in jail, the magistrate can preside over the trial and sentence the defendant only if the defendant agrees and waives the right to be tried by a district judge.⁶ That consent requirement is a recurring theme in magistrate authority. The more serious the stakes, the more likely the parties need to opt in.

Civil Case Duties

Discovery and Pretrial Management

Civil lawsuits generate enormous amounts of pretrial work, and magistrates absorb most of it. The bread and butter is discovery disputes: arguments over which documents a party has to produce, whether a deposition can go forward, or how to handle electronically stored information. District judges can refer virtually any nondispositive pretrial matter to a magistrate, and the magistrate’s ruling binds the parties unless it is clearly erroneous or contrary to law.⁶ Discovery fights are frequent and fact-intensive, so this is where magistrates spare the system the most time.

Settlement Conferences

Magistrates also conduct settlement conferences, acting as a neutral third party to help opposing sides find common ground. Many cases that look headed for trial settle in these conferences because the magistrate can give both sides a candid assessment of strengths and weaknesses, something the trial judge often avoids doing to maintain neutrality. This function alone probably resolves more cases than any other single thing magistrates do.

Civil Trials With Consent

When all parties agree, a magistrate judge can preside over a full civil trial, including a jury trial, and enter a final, binding judgment. The statute is explicit: the magistrate may conduct “any or all proceedings in a jury or nonjury civil matter and order the entry of judgment.” Consent has to be voluntary, and the court must tell the parties that refusing to consent carries no negative consequences. Appeals from a magistrate’s judgment in a consent case go directly to the circuit court of appeals, the same as any other district court judgment.⁶

Small Claims in State Courts

In many state court systems, magistrates preside over small claims cases, disputes involving relatively small dollar amounts with simplified procedures that let people represent themselves. The monetary caps vary widely, ranging from a few thousand dollars to $25,000 or more. The magistrate hears testimony, reviews evidence, and issues a binding judgment. These proceedings tend to be informal compared with regular civil court, and unpaid rent, minor property damage, and breach of small contracts make up most of the docket.

What a Magistrate Cannot Do

The clearest line is felony trials. Magistrate judges do not preside over them; those stay with district judges.⁷ Magistrates do handle preliminary and post-conviction proceedings in felony cases, and many courts authorize them to take guilty pleas in felony cases with the defendant’s consent, but the trial itself goes before a district judge.

Certain pretrial motions are also off-limits for a final decision. Summary judgment motions, motions to dismiss, motions to suppress evidence, and motions involving class certification all require a district judge’s final approval. A magistrate can hold a hearing, evaluate the evidence, and write a detailed recommendation, but the district judge makes the ultimate call.⁶

Consent is the mechanism that expands a magistrate’s reach. Without consent, a magistrate cannot try a civil case, cannot try a Class A misdemeanor, and cannot conduct a jury trial in any context. With consent, all of those are on the table.⁶ The consent rules protect your right to have a case decided by a presidentially appointed, life-tenured judge, a right you can waive, but only voluntarily.

How a Magistrate Differs From a Judge

The biggest practical difference is scope. A district judge can preside over virtually any case. A magistrate handles preliminary matters, specific categories of cases, and proceedings a judge delegates. Federal magistrate judges are appointed by the district court judges they serve and hold renewable eight-year terms rather than the lifetime appointments Article III judges receive.⁸ State-level magistrates are selected through varying processes, but most are appointed by other judges rather than elected.

Finality is the other difference. When a district judge rules, that order binds the parties unless overturned on appeal. When a magistrate rules on a dispositive matter — a motion that could end the case, like a motion to dismiss or for summary judgment — the ruling comes out as a recommendation. Parties get 14 days to object, and a district judge then reviews the disputed portions from scratch.⁹ For nondispositive pretrial matters, the magistrate’s order stands unless a party shows it was clearly erroneous or contrary to law.⁶

1
Legal Information Institute. Federal Rules of Criminal Procedure Rule 41 – Search and Seizure
2
Congress.gov. Amdt4.5.2 Neutral and Detached Magistrate
3
Office of the Law Revision Counsel. 18 USC 3142 – Release or Detention of a Defendant Pending Trial
4
Legal Information Institute. Federal Rules of Criminal Procedure Rule 5.1 – Preliminary Hearing
5
GovInfo. 18 USC 3401 – Misdemeanors Application of Probation Laws
6
Office of the Law Revision Counsel. 28 USC 636 – Jurisdiction, Powers, and Temporary Assignment
7
United States District Court District of Connecticut. What Does a Magistrate Do in Civil and Criminal Cases
8
United States Courts. Types of Federal Judges
9
Legal Information Institute. Federal Rules of Civil Procedure Rule 72 – Magistrate Judges Pretrial Order