Teodor Diaconu, 24, was arrested when immigration officers swooped on Netto Foods' industrial unit in Drayton Fields, Daventry, on August 11.
As they were checking the immigration status of the staff working there, Diaconu produced a forged Italia
n passport in another man's name and was arrested.
Alex Bull, prosecuting at Northampton Crown Court, said his locker was then searched and a forged Romanian driving licence, also in a false name, was found.
When Netto's company records were checked, they showed he had used the fake EU passport to gain work since October 2006, earning more than £38,000 before tax.
Judge Richard Bray said: "I just wish they had more careful scrutiny at these places because they must have known he was potentially an illegal immigrant.
"Far too many people are being employed with these false documents. This defendant should be deported. He's done very well out of this country."
By having an EU passport, Diaconu was able to stay and work in the UK despite over-staying his visa.
Diaconu, of Oakley Street, The Mounts, Northampton, pleaded guilty to two offences of having false documents with intent and was jailed for a year.
Judge Bray added: "I will be making a recommendation for deportation in any event because you do not have any close ties to this country."
Richard Holloway, defending, said Diaconu had worked hard, paying income tax and national insurance since his tourist visa ran out in October 2006.
The full article contains 272 words and appears in Northampton Chron & Echo newspaper.
