The Chelsea bombing Saturday night is not just a textbook case of breaking-news reporting (and police work). It’s also a handy news peg — a compelling reason to do a particular story right now — for an explainer on basic legal terminology.

First-semester students are already turning in stories involving the police, crime and the justice system. Since legal systems vary widely around the world, it seems a good time to introduce new international students to U.S. legal terms commonly used in journalism — and for Americans to brush up.

At least two international students made a mistake that is so common it’s almost universal. One newcomer recently wrote that a 16-year-old from Staten Island had joined an arts program for people on probation two years ago when he was arrested for holding a knife. And last year another student wrote:

She was arrested for arranging or attending demonstrations against President Bashar al-Assad and “spreading false news.”

The cardinal rule: Do not say arrested for. Here’s why:

One of the basic principles of American law is that people charged with crimes are presumed innocent until proven guilty in a court of law. So at this moment, legally, Ahmad Khan Rahami is considered not guilty in the Chelsea case, even if he is locked in a jail cell. If he is convicted in court, then he will be considered guilty — but not before.

The wording arrested for implies guilt, so instead journalists often say arrested in — short for arrested in connection with a crime.  Consider the lede headline on the New York Times homepage at one point on Monday:

Ahmad Khan Rahami Is Arrested in Manhattan and New Jersey Bombings

Correct.

Before the arrest, Rahami was a suspect in the bombing — that is, someone suspected of having committed the crime. (Non-native speakers: the verb is pronounced sus-PECT, the noun SUS-pect.) Once he was arrested, he was accused of or  charged with the crime. At some point he will be indicted (pronounced in-DIE-ted) — formally charged in court.

A person of interest is someone possibly involved in a crime who has not been arrested or charged. In the Chelsea investigation, the term was used to describe the five people in a car stopped on on the Verrazano-Narrows Bridge. A person of interest may or may not be a suspect, and may be wanted mainly for questioning — for example, as a potential witness.

Many journalists think they can safely describe those accused of crimes with phrases like the alleged murderer, the accused killer, the suspected embezzler. But in fact you are still calling the accused a murderer, killer or embezzler — just adding an adjective to soften the blow. You are still leaving yourself open to accusations of unfairness or, possibly, libel if those charged are not convicted. Instead, specify the legal charges or accusation, or say who is doing the accusing:

He had been charged with first-degree murder.
He is accused of killing . . .
Federal investigators say he embezzled . . .

Here’s how The Times worded the lede that ran under the headline above:

The man believed to be responsible for the explosion in Manhattan on Saturday night and an earlier bombing in New Jersey, Ahmad Khan Rahami, was taken into custody on Monday after he was wounded by gunfire in an encounter with the police, according to law enforcement officials.

The man believed to be responsible is another way of saying suspect. Taken into custody is another way of saying arrested. Neither implies guilt. I would have done some editing on that 47-word sentence, but the language is sound.

Now, here’s how those students could have fixed their copy:

. . . he was arrested while holding a knife. (He admits holding the knife and was arrested while he was.)

And:

She was accused of (or charged with) arranging or attending demonstrations . . .

While Rahami awaits trial, he may stay in jail or be released on bail, in his case set at $5.2 million. Bail is money put up as security to guarantee that people charged with crimes will not flee before trial if they are let out of jail. If they cannot raise the money, they remain in jail in lieu of (in place of) bail.

Disclaimer: The above represents knowledge amassed from 30-plus years of newspaper editing, not law school. Any corrections from legal scholars will be most welcome.