Clarence Aaron's mother said in a PBS documentary she thought her son would get probation. Instead, he got life. Screenshot/PBS Attorney General Eric Holder announced some major changes Monday to how the Justice Department handles mandatory minimum sentencing for drug crimes. Essentially, it won't enforce them anymore for many nonviolent offenders.

On a federal level, mandatory minimums for drug offenses are known as the "three-strikes-and-you're out" laws. On the third drug charge, offenders caught dealing a certain amount of drugs get slapped with life in prison.

We've listed some of the most outrageous cases below. These five people will spend their entire lives behind bars unless their cases are reviewed.

1.) Timothy Tyler was sentenced to die in prison at age 25 after selling acid to a police informant. To be fair, he sold a lot of it — 13,045 hits, according to a pre-sentence memorandum. But he only made about $4,000 and had never been in prison before. Psychosis and bipolar disorder also complicated his case.

2.) Clarence Aaron has sat behind bars since 1992 serving three consequence life sentences for conspiring to distribute crack, according to PBS. Even though he was the lowest person in a supposed drug conspiracy, he received the harshest possible punishment for the crime. Out of the four people involved in the deal, only the supplier is still serving time, according to PBS. Aaron is hoping for President Obama to grant him clemency.

3.) Sherman Chester got life in prison after his drug third offense. Even though he was only a street-level dealer, he was held accountable for nearly all of the drug deals that landed him in handcuffs — selling four kilograms of heroin and 57.4 kilograms of cocaine. The judge on the case even admitted he didn't deserve his sentence, according to Families Against Mandatory Minimums (FAMM). Unfortunately, federal mandatory minimum laws tied his hands.

4.) Stephanie George was sentenced to life in prison without parole at age 27 after the police found a lockbox of cocaine in her attic. The judge on the case defined her role as "a girlfriend and bag holder and money holder but not actively involved in the drug dealing, so certainly in my judgment it does not warrant a life sentence," The New York Times reported. Once again, federal law forced the judge's ruling.

5.) Kenneth Harvey is serving life behind bars for flying with a vial of cocaine strapped to his leg. The first two times he got caught with drugs, the court gave him probation. Judge Howard Sachs found Harvey's disproportionate sentence troubling, but he didn't know of an authority "that would permit a difference sentence," he said, according to The New York Times.

In 2010, almost 20,000 prisoners were convicted of an offense that carried a mandatory minimum, according to a 2011 Congressional report. Two-thirds of them were drug-related.

Laws like these help make the U.S. incarceration rate the highest in the entire world.

Holder's reforms didn't actually change the minimum sentencing laws — that would require Congressional approval. Under his guidelines, though, mandatory minimums won't apply to low-level, nonviolent offenders who aren't part of gangs or drug cartels.