An ambiguously worded rule book is defining the battleground in a court fight between the BIU and Stevedoring Services.

The union is seeking to overturn a Supreme Court ruling which says it broke the law by enforcing an overtime ban in February 2000.

The conflict centres around work stoppages, and long standing BIU grievances that Stevedoring Services managers had been forcing staff to work overtime.

The company claims the issue was never about forcing people to work overtime, but whether or not the union was indulging in illegal industrial action in short of a strike.

In the Court of Appeal yesterday BIU lawyer Alan Newman argued that for the action -- known as industrial action short of a strike -- to have occurred it had to be in the context of the docks being an essential service.

Mr. Newman said it was not proven that the docks were an essential service -- only that some of the items which landed on it were essential.

But company lawyer Alan Dunch said the union had not denied the docks were an essential service before and that Vice President Chris Furbert has said as much during the Spring hearing.

The union quoted English case law which it said proved overtime could not be made obligatory.

Mr. Newman quoted the collective bargaining agreement which said that the normal working week was 37 1 hours, Monday to Friday. He said: "I could almost sit down now, it seems extremely clear this is the normal week, anything else is optional.'' He quoted the Bermuda Constitution which said a person wasn't required to worked as forced labour, while European law also condemned it.

A letter which sparked the February overtime ban had complied with the rule book, said Mr. Newman by giving five day's notice and stating the time period -- in this case until stated grievances were resolved.

One section in the rule book known as the collective bargaining agreement forming the crux of the case cited by the union reads, "...it is further agreed that the men "may work'' extra hours when required.'' However, Mr. Dunch pointed to another section which said employees were obliged to notify the employer if they couldn't work overtime or they would be disciplined while another section said there will be overtime when required.

Assistant Justice Clough said: "Both sides can identify arguments to support their case, they go both ways.'' Mr. Dunch said later: "My friend was somewhat charitable when he said the collective bargaining agreement was inelegantly drafted.

"This document has not been drafted by lawyers.'' However Alan Dunch said the union still misunderstood what the case was about by focusing on overtime.

He said Judge Meerabux had ruled in the company's favour in April because the union had acted unlawfully.

But he also said docks were vital to the livelihood of Bermudians and that failure to work overtime led to serious disruption of the docks.