The Times is doing a series of articles highlighting common laws and rules. Today, in part one of a two-part series on prosecutors, we examine how prosecutors decide whether or not to charge a person. Next week, we examine why there are plea agreements and why people receive the sentence they do. To suggest a law for The Times to highlight, contact the writer.

A truck driver runs a red light and kills a person in a car.

A woman accuses a man of rape

A child reports being molested by a relative.

In each case, it's not guaranteed that charges will be filed. But what the public doesn't understand is that there are some very good reasons why prosecutors make the decisions they do, Porter County Prosecutor Brian Gensel said.

Gensel said police officers out in the community make the vast majority of decisions about what to charge a suspect with in lower-level cases. Prosecutors generally go along with the officers' decisions, but prosecutors can add charges, amend charges or decline charges.

With more serious offenses, such as murder and rape, police and prosecutors work together during the investigation and prosecutors eventually decide whether to file charges.

Gensel said the decision of whether of not to charge a person is made based on:

- Whether prosecutors believe the person did the crime,

- Whether there is enough evidence to convince a jury of the person's guilt beyond a reasonable doubt.

In addition to these criminal laws, prosecutors also look at case law, which is what previously happened in the court system with similar cases. If a trucker runs a red light and kills someone, were the trucker's actions criminally reckless according to legal precedent?

Gensel said a trucker who was going 100 mph more than the speed limit, who was running from the cops or who intoxicated was obviously criminally reckless. A trucker who dropped an item on his floorboard, looked down and ran the red light probably would not be.

"It has to be quite egregious and quite beyond what we all accept as normal driving behavior," Gensel said.

In cases where prosecutors don't believe the trucker's actions were criminal, the trucker can still face a civil lawsuit.

Sex crimes constitute the other difficult area for prosecutors, with crimes against children being especially difficult because they have a difficult time testifying and because there is often no witnesses to support their story. Prosecutors hope to have something independent of the child's testimony -- like physical evidence -- to proceed.

Acquaintance rapes also are difficult because of conflicting stories and because drugs or alcohol are often involved.

In cases where the law doesn't allow police or prosecutors to seek charges against someone, they will often work with lawmakers to change the laws. For example, police in Porter County pushed for a law making it illegal to disarm a police officer after such an incident occurred in Porter County. A law making it illegal to disarm an officer went into effect July 1.

But there are some cases in which injustices will likely never be crimes, Gensel said. For example, despite multiple instances of truck drivers running red lights and killing people, legislators will still find it hard to make things that almost everyone has done in their life -- like speeding or running a red light -- a crime rather than an infraction.

"Just because the outcome is horribly tragic doesn't mean the behavior that caused it was criminal and that the law needs to be changed to address it," Gensel said.