SINGAPORE - The kidney specialist who underpaid more than $1.4 million in taxes, after under-declaring his income, will now have to pay a further $1.8 million in penalties and a fine in addition to making full restitution to the taxman after he pleaded guilty on Friday (Aug 30).

Lye Wai Choong, 60, the director of the Centre for Kidney Diseases, admitted to six counts of tax-related offences - two for abetting his centre in omitting business income without reasonable excuse and four for filing incorrect Goods and Services Tax (GST) returns.

Nine similar charges were taken into consideration during sentencing.

A district court heard that the offences started in 2011, when Lye's centre filed incorrect GST returns for 12 quarters until December 2013.

His centre also omitted certain business income from tax returns between 2012 and 2014 without reasonable excuse.

Court papers stated that Lye employed a Ms Norma Wati Suari to handle finance and administrative matters. Ms Norma had told patients to make payments directly to Lye instead of the centre.

As a result, these payments did not appear in the centre's tax books. Lye also did not declare the money in his own personal income tax returns.

The amount of income omitted through such methods was close to $6 million, resulting in the undercharging of $1 million in income tax, said court documents.

"The accused was the controlling mind of the centre," said court papers, which noted that Lye knew about the payments and deposits made and did not ensure the accuracy of the tax returns.

In addition, the centre also failed to account for GST of $419,426 after it gave "incorrect information as to its liability" for the tax.

"As director of the centre, the accused had not shown that he had exercised due diligence in ensuring that GST was properly reported in the GST returns of the centre," said court papers.

The penalties - which are twice the sum of undercharged tax - came to around $1.8 million. Lye was fined an additional $21,000.

He could have been fined a maximum of $5,000 and jailed for up to three years for each of the six guilty charges in addition to paying penalties that amount to twice the sum of undercharged tax.

Lye has made full restitution of the taxes owed.