Federal Regulations on Digital Checks

Uniform Commercial Court (UCC) Regulations on Checks state that, as long as a Check conforms to its definition, it is a legal tender and bank tellers are required to accept it when presented at a Bank. 

Banks, then, have some discretion on the amount of time they will hold the funds before releasing them.

The Check21 definition of a Check as defined per Federal Government states that a check image reproduced cleanly in any paper is as valid as the traditional Paper Check.