Strictly speaking, a document must be presented as an original to be valid. Why is this the case?
The original paper, watermark, official seal, chip, and other anti-counterfeiting measures must be intact to prove (or demonstrate) that it is the genuine article, which in turn proves that you possess the necessary qualifications and abilities.
Copies? But it's just a single A4 sheet of paper, what could an A4 sheet possibly do to prevent forgery?
No matter what, if you take it seriously, you will be committing a crime because the authority lies with them, not with you.
Therefore, it should always be carried with you.