7 Answers

One word.

YES!

Theodore John "Ted" Kaczynski, also known as the "Unabomber", is an American mathematician, social critic, and Neo-Luddite who engaged in a mail bombing campaign that spanned nearly 20 years, killing three people and injuring 23 others. Wikipedia

His house was confiscated and hauled off to the FBI Crime Lab for meticulous study. 

Probably.

The police returned to a building in NYC 30 years later to get DNA samples...they tore up a floor and actually found some- wild.

YES!!!

Yes, no telling what they could find as technology gets better and better. Like, we have DNA sampling now......

Yes, they would.

As Doolittle says, DNA can last for a very long time and 

the technology they have today to analyze collected evidence 

is really mind-boggling.