Former Newshub political editor Tova O'Brien is awaiting an Employment Relations Authority (ERA) decision which will determine when she can begin hosting a new radio show with MediaWorks.
O'Brien has contested a restraint of trade clause in her contract with Discovery, which would prevent her from launching her new breakfast talk show at MediaWorks for three months.
The contractual clause is based on the notion that O'Brien is teaming up with a direct competitor of Discovery's Newshub.
But the journalist, who had been with Newshub for 14 years, has argued to the ERA that her soon-to-be role as a breakfast radio host is not similar to her role as political editor on TV3.
She took the dispute to the ERA after mediation failed. A determination is expected next week following a three-day hearing in Auckland which finished on Thursday.
Owner of Newshub, Discovery, said it is "archaic" to think that radio and television breakfast news shows are not in direct competition with one another.
Discovery argued that Newshub's The AM Show will compete for the same audiences and advertising dollars as O'Brien's new radio show with MediaWorks.
"Tova and The AM Show will be live, at the same time, on weekday mornings, meaning audiences looking for that content will need to make a choice to turn to Tova's show, the AM Show, or another show," Discovery's lawyer Peter Kiely said in closing submissions.
Kiely said O'Brien's show would run from 6.30-9am every weekday. The launch date for the new breakfast show on Today FM hasn't been confirmed but is rumoured to be this month.
In her evidence, Discovery's head of news Sarah Bristow said O'Brien would be taking intimate knowledge of Newshub to a direct competitor, potentially to its benefit, and that "breathing space" is needed.
Kiely said O'Brien was well aware of what the restraint of trade clause meant when she signed a new contract at Discovery.
"She went into the new role with her eyes open. The clause was there, and she signed it after taking legal advice.
"Tova did not make an attempt to obtain or negotiate written consent from Discovery to waive or reduce the restraints when [head of news Sarah Bristow] notified her of the clause in October."
He said O'Brien didn't seek authorisation from Discovery - who is still her employer - to release a direct quote promoting her new MediaWorks radio show in a press release.
But O'Brien's lawyer Charlotte Parkhill said her client endured "bullying" in her final days with Discovery and she is "devastated" she had to take her fight to the ERA.
"Why would you want to become a talented person if your employer can trap you for months on end?
"It is not in the public interest for Tova to be restrained from working in her chosen profession."
Parkhill said skill and talent should not be restrained, and the "only possible benefit" of the restraint of trade would be to cause a competitive disadvantage to MediaWorks.
Discovery's refusal to engage in O'Brien's offer of taking annual leave near the end of her time at Newshub was "unfair", Parkhill said.
"This is bullying by Discovery, and she is devastated to be here fighting this case."
O'Brien announced her resignation at the beginning of November last year in time to finish at Discovery before Christmas, take a month's leave, and finish her contract in time for Today FM's launch by the end of this month.
But Discovery said a sudden departure of a political editor would have been detrimental to Newshub, and enforced the three-month restraint of trade.
O'Brien often appeared on The AM Show and was broadcast on TV3 and Magic Talk radio - harking back to when MediaWorks owned the radio and TV networks.
Restraint of trade clauses are designed to prevent employees from jumping ship to work for a competitor.