Prime Minister Arlene Foster has called for tougher sentences for those convicted of murdering officials, including police officers, prison guards, soldiers and health workers.
NI has the most lenient tariff in the UK and Ireland for this crime.
In August, a 40-year sentence was handed down in the Republic for the murder of a policeman, but in NI the starting rate is 15 to 16 years.
Ms Foster said it was “morally indefensible” in the Belfast Telegraph.
Speaking to BBC News NI’s Good Morning Ulster show later Tuesday, she said she didn’t think it was’ right or fair ‘and that Stormont needed’ to take a very serious look at it “.
Aaron Brady, from Crossmaglen, County Armagh, was convicted of the murder of garda (Irish policeman) Adrian Donohoe, who was shot dead during a robbery in County Louth in 2013.
To be found guilty of the offense, the jury had to be satisfied beyond a reasonable doubt that Brady knew he was shooting a guard while on active duty or was reckless as to whether or not he was a guard.
The crime of capital murder in the Republic of Ireland carries a mandatory minimum sentence of 40 years.
In England and Wales it is 30 years and the crime carries a minimum sentence of 20 years in Scotland.
“Yet in Northern Ireland that figure is less than half,” said the Prime Minister.
“This has worried me for some time.
“It is important that our justice service is adapted to its needs.
“The justice system must deliver justice to the victims, to those people who have been wronged, and it must reflect the harm done.
“It has to have a deterrent effect in order to deter people from committing this crime and there has to be an element of rehabilitation. “
‘A very clear message’
Ms Foster said it was important that a “very clear message” be sent to those involved in republican dissident activity in Northern Ireland “that if you murder an official you go to jail for a very long time”.
“Unfortunately, I don’t think that message is there yet. ”
In 2016, then Justice Minister Claire Sudgen launched a major review of sentencing in Northern Ireland.
The premier said she hoped to meet with Justice Minister Naomi Long to discuss the matter soon.