To whom it may concern:
Delaware + Arkansas
dear
Crazy, like a certain cartoon duck
(5)
daffy
These octagonal warnings weren't always red; some were yellow until 1954
stop signs
Reacting to hemoglobin, the chemical Luminol is used to detect this, even if it's been wiped off
blood
"Miss Poppins Once Owned One Tiny Baby Sheep"
"Mary Had A Little Lamb"
Dark:
Indiana + Kentucky
inky
Permanently leaving the military without permission
(9)
desertion
The red flyer is a large type of this marsupial
a kangaroo
A specialized lab is used for toxicology, the detection of these, from the Latin for "drink"
poison
"Glimmer, Glimmer, Small Heavenly Body"
"Twinkle, Twinkle, Little Star"
A party:
Georgia + Louisiana
gala
It goes on salads or on wounds
(8)
dressing
It took years to get a shot of the red aurora borealis; charged particles in the "wind" from this celestial body collide with oxygen in Earth's magnetic field to produce the hue

The Sun
A forensic expert "dusting" a room is checking for these "digital" clues
fingerprints
"A Trio Of Vision-Impaired Rodents"
"Three Blind Mice"
Has a white face:
Michigan + Maine
mime
Any tyrannical ruler
(6)
a despot
He was the father of Leif Eriksson
Erik the Red
This word for a public official who investigates all non-natural deaths comes from the Latin for "crown"
a coroner
"An Elderly Scotsman Owned One Ranch"
"Old MacDonald Had A Farm"
Think of a bouquet:
Florida + Oregon + Alabama
floral
Pre-Christian Celtic priest
(5)
a druid
In issues of French Vogue you read a lot about people on le tapis rouge, this
the red carpet
In a forensic lab, a hood eliminates fumes & prevents the intrusive process called "cross" this
cross-contamination
"One Grizzly Ventured Across A Summit"
"The Bear Went Over The Mountain"