Applicant gets visa with fake documents

When exactly do things like Skills Assessment and English Language proficiency test documents get checked by the department of immigration? The answer apparently seems to be well and truly after the visa has been granted.
In a matter recently considered by the AATA, the Tribunal found that the DIBP granted the applicant a skilled visa purely based on information provided by the applicant at the time of application. There were no checks made by the DIBP with the Skills Assessment authorities or the relevant language testing centre prior to the DIBPs decision to grant the visa.
However, a year after the application and well after the grant of the visa, "CPA Australia advised the Department that in their database they had no record of the applicant’s skills assessment, that they had no record of the reference number provided by the applicant, and no record of the applicant’s name” according to the Tribunal member's statement.
The Department, then undertook checks with the IELTS Report Form Verification Service which showed that there was no record of the applicant undertaking an IELTS English test - the Verification Service was unable to locate any record of the reference number the applicant provided and there was no record of the applicant’s name in their database.
DIBP subsequently cancelled the visa. The applicant applied for a review denying any wrong-doing and pointed to corruption within the DIBP and fraud by “a migration agent whom he paid a fee of $70,000…”.
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