Congressional Budget Office Cost Estimate: H.R. 2884: Victims of Terrorism Tax Relief Act of 2001 [open pdf - 9KB]
"H.R. 2884 would provide specialized income tax treatment to individuals who die as a result of injuries or illness from the terrorist attacks of September 11, 2001, and April 19, 1995, or attacks involving anthrax between September 11, 2001, and December 31, 2001. All individuals who qualify for such treatment would receive a $10,000 minimum benefit regardless of tax liability. In addition, H.R. 2884 would reduce estate taxes for those individuals who die as a result of injuries or illnesses from such attacks. This treatment would be similar to that provided to members of the armed forces who die as the result of terrorist or military activity outside of the United States. The act would also change the taxation of certain benefits related to death or injury."
Congressional Budget Office: http://cbo.gov