Why do we have Statutes of Limitation..

especially for major felonies.

I ask because here in Chicago, there are news articles about a guy who robbed 16 banks and that on Dec 7th the 5 year SoL runs out and after that he's scott free.

To me this makes no sense.

I would imagine it's because the farther out you get from a case the harder it is to prosecute it.

That should be a decision a prosecutor makes. Not all crimes have SoL either. I just don't get the logic of saying if a bank robber can evade capture for 5 years, he's good to go for life.

Think of how much taxpayer money it's saving.