Any individual who knowingly possesses a controlled substance that is listed in section 841(b)(1)(A) of this title in violation of section 844 of this title in an amount that, as specified by regulation of the Attorney General, is a personal use amount shall be liable to the United States for a civil penalty in an amount not to exceed $10,000 for each such violation.

The income and net assets of an individual shall not be relevant to the determination whether to assess a civil penalty under this section or to prosecute the individual criminally. However, in determining the amount of a penalty under this section, the income and net assets of an individual shall be considered.