The new, $240-million Social Assistance Management System (SAMS) last week erroneously queued up $20 million in welfare and disability support overpayments, but only about $300,000 was actually sent out.
The Progressive Conservatives and New Democrats said others who depend on social assistance got far less than normal or didn't get any payment, and accused Social Services Minister Helena Jaczek of being out of touch.
"There needs to be apologies to those people who are not going to get their payment and to those who have overpaid," said PC critic Bill Walker. "This is just another bungled project under their administration."
"Here we have a government that is so arrogant that they're not even prepared to apologize for this mistake, nor can they guarantee that it's not going to happen again," said NDP Leader Andrea Horwath.
Jaczek said the SAMS computer error involved overpayments averaging about $1,100 each, but insisted the fact some people got less than normal, or no payment at all, was not related to the glitch with the new system.
"Out of 570,000 cheques, occasionally there are administrative errors, and people are obviously encouraged to immediately contact their case worker if they have a concern related to an underpayment," she said.
Pressed by reporters, Jaczek eventually said she would apologize, but only on a case-by-case basis if someone takes their complaint directly to her.
"If there's an individual who tells me their particular situation I will certainly apologize to them on an individual basis if they have suffered from some hardship," she said. "It was a very unfortunate event, and I continue to try to rectify the situation as well as a I can."
Horwath was concerned some welfare and disability payments will be wrong again later this month when they are sent out early because of the Christmas holidays.
"Christmas is just around the corner and I'm very worried from what we saw just happen that we might end up in the same situation," she said.
The Tories said the mistake with the support payments was just the latest mismanagement by the Liberal government following computer issues at eHealth Ontario and the Family Responsibility Office.
During question period Tuesday, Premier Kathleen Wynne changed her tone in responding to the problems with the new IBM-built system that administers social assistance payments, after insisting Monday it just a glitch that impacted only one per cent of recipients.
"I am not minimizing in any way the impact on individual families," Wynne told the legislature. "It is not acceptable that certain families would have had to undergo this problem, and we are working as hard as we can to make sure that those situations are rectified."
Both opposition parties said the Liberals ignored repeated warnings from caseworkers represented by the Ontario Public Sector Employees Union about the complicated new software and how it was not ready to go online.
"You knew there were problems and it's obvious they weren't fixed, but you went ahead anyways," said Walker.
The Liberals dug up stories from 2001, when OPSEU staged protests about the last social assistance computer system, the one the government said was totally outdated and needed to be replaced with the new SAMS program.
"We are introducing a new system that will help those individual families ... to get better service because caseworkers will be able to spend more time with them once this system is updated," said Wynne.
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