Employers and employees face serious penalties if they are caught engaging in illegal working practices.
Alison Davies, an associate at Steeles Law, explained that while it was up to employers to make deductions for tax and National Insurance, employees could also be held responsible if it was found they were aware that any such deductions were not being made.
She said: "Provided the employer deducts them from the employee's wages, an innocent employee will not suffer if the employer fails to pay them to the Inland Revenue.
"However, an employee who deliberately cooperates in an illegal arrangement with the employer to evade payment commits a separate offence."
Ms Davies said that employers engaging in such practices could be fined up to £1,000.
And, she added, employees who help their bosses in any scam may find that they are not protected by employment law.
This would mean they would not be able to claim compensation if they were unfairly dismissed.
In 2004 Professor Colin Talbot of Nottingham University estimated that the black economy in the UK could be worth between £53 billion and £137 billion a year.
