Japanese courts have reported a growing rise in the number of tax expense lawsuits over the past few months. Most of these lawsuits originate from gamblers who have lost significant sums of money gambling at casinos or horse racing tracks.

Last year Osaka High Court charged a Japanese man of tax evasion to the amount of 570 million yen ($4.7 million). The prosecutors proved that this man began purchasing online betting slips between 2007 and 2009 that allowed him to earn as much as 3 billion yen.

The defendants lawyers countered that if his winnings were considered as income and made taxable, then his loses and expenses incurred while gambling must also be considered. A number of other gamblers have followed suit and filed similar petitions.

There has been no word recently on casinos becoming legal and regulated in Japan.