Not long ago, reporter Sonya Paul was working on a story about caste discrimination in California.

Cast is a tradition that comes from India. It's a hereditary identity where some people are at the top of society and some are at the bottom.

Anyway, Sonya asked a source, have you ever experienced caste discrimination here in the U.S.?

So it happens all the time.

What's the one that maybe is most outrageous or hurts the most?

The handshake.

What is the handshake?

I run into this gentleman. We shake hands, he's holding a tissue in his hand, right where he states his caste.

Then he says, you have to hold a tissue.

You never know who you shake in hands with.

I said, really, I am that untouchable.

I'm that untouchable.

Now the state of California wants to make this caste discrimination illegal.

That's coming up on Today Explained.

I went to the precinct and I said, look, I wanted to talk a lot of murder that I think happened.

In 1993, Trevel Coleman shot a man, but was never a suspect.

He kept the secret for years and years.

I've heard of people turning themselves in, but it's usually, soon thereafter the crime,

I've never experienced anything like someone coming forward 17 years after the fact.

So no, this is absolutely extraordinary.

Here Trevel's story on the latest episode of Criminal.

Listen, wherever you get your podcasts.

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