The government is expected to reduce the age of consent to 16, when it launches a report on teenage sexual activity and child protection next week.
It has been carried out by the all-party Oireachtas committee on child protection, which was convened after the current law on statutory rape was struck out during the summer.
The government was forced to address the issue of the age of consent earlier this year, when the Supreme Court ruled the existing legislation was unconstitutional.
It is understood the Oireachtas Committee on Child Protection will recommend that the age be lowered by one year to 16 when it launches its report on Thursday.
There will be an exception for adults in authority, such as teachers and sports coaches, who will be liable for prosecution if they have sex with a teenager under 18.
The DPP will also be given more discretion in deciding whether to prosecute younger teenagers who engage in sexual activity.
A lowering of the age of consent will be opposed by groups such as the Rape Crisis Network, which has been lobbying for it to remain at 17.