The one-time member, who quit soon after being appointed to the tribunal, says the government's focus on hearing cases as quickly as possible is to the detriment of ailing or unemployed Canadians denied employment insurance, Canada Pension Plan or old-age security benefits.
"You want the person hearing your case to consider the facts carefully, who isn't going to feel rushed or resentful because of the workload," said the former member, who spoke on condition of anonymity for fear of possible reprisals.
The old regime was "client-motivated and client-driven," the person said.
"Fairness to the client and fairness of the process was one of the key pillars, and was something that was always to be considered. Under the new process, I never did hear that — it was all about production and getting cases done."
A spokeswoman for Employment and Social Development Minister Jason Kenney disputed the criticisms, saying the new system has accelerated the process for employment insurance appeals in particular.
"The old appeals process for employment insurance was expensive and slow; fewer than one in three claims were heard within 30 days," Alexandra Fortier said in an email.
"The reduction of the number of appeals is largely attributed to the new reconsideration process for EI refusals. Under the new process, approximately 90 per cent of the clients who request a reconsideration do not pursue any further type of appeal."
The tribunal, established in April 2013, replaced four other separate panels that heard appeals on social security rulings.
But the former member suggested that some of the government's 72 full-time appointees to the SST lack the skill set needed for the job. Several of those appointees have donated money to the party in the past.
"You have to have insight — into the legal aspects, the law and the precedents — and you have to bring that into your decision-making," the person said.
"You require a certain expertise and I would say that a number of individuals that were appointed, like a lot of government-in-council appointments — they do not necessarily have that."
The government has made good on a promise to save taxpayers more than $20 million a year under the new system. But the tribunal is also hearing fewer appeals and is struggling with a backlog of more than 10,000 cases.
In addition to 72 full-time members, the feds have hired 22 part-time employees to help with the backlog of Canada Pension Plan disability and old-age security cases.
"It was a frustrating place to work," the former tribunal employee said. "They want the stars and the moon."
Liberal employment critic Rodger Cuzner said the individual's insights show what a mess the government has made of the system.
"The tribunal is a perfect example of callous incompetence by this government — not only costing taxpayers more but hurting vulnerable Canadians in the process," Cuzner said.
Follow Lee-Anne Goodman on Twitter @leeanne25