How reliable are fingerprints on paper

Question

I received a letter full of racial slurs and threats. When I held the cardboard sheet of paper up to the light, I only saw 3 prints where I touched it.

If they fingerprinted the envelope and the culprit had a record, how likely is it this will be taken care of?

Answer 1

If they can lift the prints, they will be used.  The problem with prints on paper is how long ago the paper was handled.  Also, anything sent through the post office has a number of people touching the envelope.  The more people with access to the paper, the less likely the prints will help.

Answer 2

Iodine fuming is usually an effective way to lift prints from paper.

However, unless you have a suspect, I doubt they will fingerprint the paper.  There is no automated database, so prints must be hand checked. That would take a considerable amount of time and resources, so it is unlikely they will bother for a single incident.