Tax fraud and evasion are serious matters. Misrepresenting your income or failing to pay appropriate taxes can carry heavy penalties including fines, jail sentences, and felony convictions. Information on fraudulent tax activity is relayed to the I.R.S. in the following ways. Most often, the Criminal Investigation Division of the I.R.S. will uncover suspicious activities while prosecuting guilty tax offenders. Informants hoping to gain financial reward will often notify the I.R.S. of friends and colleagues falsifying tax returns. Banks are also obligated to notify the Internal Revenue Service of certain questionable transactions. Regardless of how the crime is discovered, there are substantial legal and financial penalties if you are caught in criminal tax activities. If you have any questions about your taxes, or the possibility of a criminal tax matter, consult a tax specialist or tax attorney.

fraud
[uncountable and countable] the crime of deceiving people in order to gain something such as money or goods

evasion
[uncountable] when you deliberately avoid doing something that you should do, or paying an amount of money that you should pay.

felony
plural: felonies, [uncountable and countable] law:
a serious crime such as murder

tax evasion
[uncountable] PET the crime of paying too little tax

misrepresent
[transitive] to deliberately give a wrong description of someone's opinions or of a situation:

falsify
past tense and past participle: falsified,
present participle: falsifying,
third person singular: falsifies
[transitive]
to change figures, records etc so that they contain false information:
Eg. The file was altered to falsify the evidence.

税务欺诈和逃税属于情节严重的犯罪,虚报收入或者少交应纳税额可能受到严厉的惩罚,包括罚款、蹲监狱或被判重罪。税务局通过以下几种方式可以知道你是否从事了税务欺诈行为。最常见的一种方式是,税务局刑事调查部门在起诉税务被告时可以揭发其所从事的可疑行为。（第二种信息来源来自）想得到报酬而将朋友和同事虚填纳税申报单通知税务局的人。（第三种信息来源来自）银行有义务提交有关方面存在问题的报告给地方税务机关。不论犯罪行为是如何被发现的,一旦你在税务方面存在犯罪行为,就会受到法律以及经济上的制裁。如果你存在税务问题,或者在税务上有触犯刑律的可能,（务必）向税务专家或者是税务律师联系。