After listening to arguments from lawyers representing the Scottish Secondary Teachers' Association, which brought the case on behalf of nine women teachers, the law lords decided on Tuesday that Ian Truscott, the authorities' QC, did not need to speak.
Linda Marsh, the former Strathclyde education officer who has been handling the long-running case, says this is normally an indication of victory. David Eaglesham, the SSTA's general secretary, was noncommittal after he flew back from London. "We want to await the judgment their lordships make in a few weeks time."
If the councils have won, they will breath a huge sigh of relief. With their continued spending crisis showing no signs of abating, they faced claims in back pay from 500 women teachers across Scotland, 400 of them in the 12 councils which replaced Strathclyde, who had been acting as principal teachers but not paid the same as men doing the same job.
The SSTA argued that this amounted to sex discrimination under the Equal Pay Act. The authorities conceded the nine women had been doing the same work as male principal teachers but said this was because financial restrictions made it impossible to appoint as many principal teachers as they would like and because the promotion structure is laid down by law.
The councils said that the underlying intention had not been to discriminate and they did not have to justify their actions in law.
Ms Marsh said: "The decision becomes a very important one for all employers because it disposes of what were essentially regrading claims that had nothing to do with sex discrimination".
The case began in 1990 against Strathclyde. The union won its case at the initial industrial tribunal and the employment appeal tribunal, but lost in the Court of Session.