Courtesy of the Word Detective:
"Dead to rights" is indeed an odd expression, dating at least to the mid-19th century, when it was first collected in a glossary of underworld slang ("Vocabulum, or...
This is a real brain tester. I do Know the origins of several other phrases, such as "The Whole Nine Yards" referring to the 9 yds of fabric used for the Scottish great kilt. ***CORRECTION*** TO "THE...