Once a person has been convicted of a criminal offence, the criminal record cannot be deleted from the police or court files (unless the offender successfully appealed against the conviction). However, under Section 2 of the Rehabilitation of Offenders Ordinance (Chapter 297), if a person who has not previously committed any offence before that person is convicted of an offence and is not sentenced to imprisonment exceeding three months or a fine exceeding $10,000, that person's conviction record will be considered as "spent" if he has not re-offended within a period of three years.
The effect of a spent conviction is that in general that person should be regarded as not having been convicted of the offence. Hence, if that person is asked by his potential employer or other person whether he/she has committed any offence before, he/she can simply say "No". He/she cannot be dismissed by his/her employer on the ground that he/she did not disclose his/her criminal record or on the ground that he/she has a conviction.
However, this spent conviction scheme is subject to a number of exceptions. For example, it does not apply if that person wants to apply for some high ranking jobs in the Government or if he wants to become a lawyer, accountant, an insurance broker or the director of a licensed bank (see Sections 3 and 4 of the Rehabilitation of Offenders Ordinance (Chapter 297) for further details of the exceptions). Moreover, if that person applies for a Certificate of No Criminal Conviction from the police for emigration purposes, the police will still disclose such criminal record in the Certificate with a note that the relevant conviction is regarded as spent under Hong Kong Law.