Licensees have been warned of the importance of asking customers to prove their age, by lawyers Poppleston Allen. The company drew attention to the increased use of test purchasers, who are not allowed to lie about their age and are generally 15 years of age. The group urged licensees to remind staff during the course of every evening of trade "to ask for identification for anyone in relation to whom there is any doubt whatsoever as to whether they are 18 or over". Any staff member who serves an underage person is likely to be given an on the spot fixed penalty of £80. The licensee is also responsible for any sales on the premises and must prove that staff had been properly trained to verify the age of customers.