Fair Work Commission Vice President Graeme Watson has broken with tradition by issuing his own separate decision on the future of paid domestic violence leave ahead of a single majority decision being made.

When Mr Watson announced his resignation in January he declared the Fair Work Commission was "partisan, dysfunctional and divided".

A former partner at law firm Freehills, Mr Watson was the last remaining Coalition appointee in a senior role at the commission and a strong dissenter in favour of business.

A day before his resignation takes affect on Tuesday, Mr Watson released his decision as one of three members of the full bench.

A spokeswoman for the Fair Work Commission confirmed it was highly unusual for a single judgement to be issued ahead of a majority decision, however his judgement needed to be delivered before his resignation. The remaining two commissioners can overrule Mr Watson's decision, or may agree.

In his judgement, Mr Watson concluded he was not satisfied that the family and domestic violence leave claim by the ACTU is necessary to provide a fair and relevant minimum safety net of terms and conditions.

"It follows that the ACTU claim should be rejected," he said.

"This matter has been before this Full Bench since November 2015. The evidence, submissions and hearings were comprehensively and completely dealt with by 2 December 2016. The other members of the Full Bench are not presently able to issue their decision."

The Fair Work Commission is reviewing the ACTU claim for an extra 10 days of paid leave for victims of domestic violence to attend legal or medical appointments and other commitments.

In his judgement on paid domestic violence leave, Mr Watson said the ACTU application seeks to introduce a form of leave that can be taken without prior approval, "and is available in a broad and somewhat uncertain range of circumstances".

"In my view this approach to the problem of domestic violence runs the risk of undermining the level of trust at the workplace and causing significant uncertainty and cost for employers," he said.

The Australian Industry Group welcomed Mr Watson's rejection of union claims for paid domestic violence leave in all awards.

"The reasoning in the decision is very sound and persuasive, and hopefully the two other Members of the Fair Work Commission Full Bench will adopt similar reasoning when they hand down their decisions," AIG chief executive Innes Willox said. "Employers have different capacities to provide support to employees who experience domestic violence in their personal lives.

"The unions' "one-size-fits-all" claim for all awards to be varied to give each employee an entitlement to 10 days paid leave per year is not appropriate."James Pearson, chief executive officer of the Australian Chamber of Commerce and Industry said it welcomed Mr Watson's decision but "we need to await further decisions from the remaining members of the three-person Full Bench to know whether awards will contain new regulation on domestic violence leave".

The ACTU declined to comment until the full bench decision was delivered.