HALIFAX -- A court hearing for three Mi'kmaw women arrested in April at a rural construction site north of Halifax and accused of violating a court injunction has been delayed until December.

The women's lawyer, Michael McDonald, says he plans to argue before Nova Scotia Supreme Court that his clients had the right to be on Alton Natural Gas Storage Inc. property, despite a March 27 injunction limiting protests to a nearby, fenced-off area.

McDonald said Monday his arguments in the civil proceedings will be based on an aboriginal title claim for the lands currently being used by Alton along the Shubenacadie River.

Originally scheduled for Aug. 15, the hearing into the alleged breach of a temporary injunction to stay off the land is now set for Dec. 16-17.

A contempt of court injunction hearing is a civil, not a criminal, matter. The complaint is filed by the company, but the RCMP carries out the arrests and provides the evidence.

McDonald said after a court hearing on Monday that the women could face fines and court costs if a judge finds they were in contempt of the injunction by Justice Gerald Moir.

The respondents' lawyer said their defence is based on the so-called "colour of right" legal principle, where a defendant argues they had an honest belief that their action was justifiable.

"We're not arguing the facts," said the lawyer in an interview outside court.

"We're saying that under Mi'kmaq law, the respondents believed those lands were Mi'kmaq lands, and they were never ceded or sold."

During Monday's hearing, Justice John Bodurtha formally added the names of the three respondents, Darlene Gilbert, Madonna Bernard and Paula Isaac, to the case.

Alton plans to use water from the tidal river to create large underground storage caverns.

The three women have said they fear the 73-kilometre tidal river, which cuts through the middle of Nova Scotia, may be polluted from the briny discharges, but the firm says they'll be within safe limits.

The original notice of motion from Alton against the three was filed on May 10, alleging they had "trespassed" on its property in contravention of Moir's original order.

Lori MacLean, a spokeswoman for Alton, said the firm has worked to engage with the Mi'kmaq since 2006 as the project was developed.

"That engagement has included a third-party independent science review that was led by the Mi'kmaq, and two Mi'kmaq ecological knowledge studies conducted by the firm Membertou Geomatics," she wrote in an email.

"With respect to today's court proceedings, Alton sites are work sites. There is a court decision and a court order in place to allow for safe access by workers to these Alton work facilities near Stewiacke."

MacLean said the company needed access to the work site to assess damage from flooding and to ensure it is responsibly maintaining the property, and it proceeded with the civil case "because of trespassing at the work site."

However, McDonald says he also plans to file an injunction asking for all work on the Alton project to stop as the legal proceedings take place.

The lawyer said he intends to call at least four witnesses at the December hearing, including one of the constables who carried out the arrests.

He says it's possible that a misunderstanding or misinterpretation occurred due to the dialect of Mi'kmaw spoken by the arresting officer, as the language can vary slightly from region to region.