Almost 2000 union members at the Ministry of Justice are voting on whether to take strike action after pay negotiations stalled.
The proposed two-hour stoppage is set to take place on 19 September. The union said it was to get a fair pay deal for low-paid and female workers.
In a statement, Public Service Association (PSA) national secretary Erin Polaczuk said the ministry did not properly value some female dominated roles.
"They do crucial jobs such as court registry officers, court reporters, victim advisors and family court co-ordinators.
"They deserve to be properly valued for the work they do in making sure the justice system runs smoothly and fairly."
According to the PSA, the average female justice employee earned 15 percent less than the average male, which was greater than the average public sector pay gap of 12 percent.
Ms Polaczuk said that was made worse by the already low ministry wages.
"These are not highly-paid workers: Last year, Justice had the third-lowest average salary in the public sector, and we believe they are slipping back even further."
The vote for strike action had not been taken lightly, she said.
"Strike action is always a last resort but our members feel like they have no other alternative.
"The PSA remains ready and willing to negotiate in order to correct this unfairness."
In a statement, Ministry of Justice chief executive Andrew Bridgman said the ministry was committed to continuing negotiations.
"We are willing to meet at any time.
"We have offered a 5 percent increase over two years, which is consistent with agreements reached by other government agencies. The PSA have asked for more than 13 percent over the same period."