What follows is an opinion from a United States Court of Appeals.
Intervenors who participated as parties at the courts of appeals should be counted as either appellants or respondents when it can be determined whose position they supported. For example, if there were two plaintiffs who lost in district court, appealed, and were joined by four intervenors who also asked the court of appeals to reverse the district court, the number of appellants should be coded as six.
When coding the detailed nature of participants, use your personal knowledge about the participants, if you are completely confident of the accuracy of your knowledge, even if the specific information is not in the opinion. For example, if "IBM" is listed as the appellant it could be classified as "clearly national or international in scope" even if the opinion did not indicate the scope of the business. 

Your task concerns the first listed appellant. The nature of this litigant falls into the category "federal government (including DC)", specifically "other, not listed, not able to classify". Your task is to determine which specific federal government agency best describes this litigant.

Opinion:
UNITED STATES v. BOOTH.
No. 5742.
Circuit Court of Appeals, Third Circuit.
July 26, 1935.
Horatio S. Dumbauld, U. S. Atty., and Stanley Granger, Asst. U. S. Atty., both of Pittsburgh, Pa.
Young M. Smith, Will G. Beardslee, Wilbur C. Pickett, and Randolph C. Shaw, all of Washington, D. C., and Charles G. Lane, Jr., of Pittsburgh, Pa., for appellee.
Before BUFFINGTON and THOMPSON, Circuit Judges, and JOHNSON, District Judge.
THOMPSON, Circuit Judge.
This is an appeal from a judgment of the District Court for the Western District of Pennsylvania. The appellee brought suit to recover on a war risk insurance policy which insured him against total and permanent disability. The premiums were paid up to April 22, 1919, and thereafter were allowed to lapse. At the trial the appellant moved for a directed verdict on the ground that the appellee had failed to sustain the burden of proving that he had become totally and permanently disabled while the policy was in force. This was refused, and the case was submitted to the jury, which returned a verdict for the appellee.
In our opinion, the evidence produced by the appellee is insufficient to prove that he was totally and permanently disabled either before or after the lapse of the policy. The testimony is uncontradicted that the appellee pursued various gainful occupations up to the time of the suit. Although medical experts called by the appellee testified that he could not possibly pursue a gainful occupation because he had suffered total and permanent disability, the evidence clearly showed that the appellee did, in fact, pursue various gainful occupations. Applying the tests set forth in Lumbra v. United States, 290 U. S. 551, 54 S. Ct. 272, 78 L. Ed. 492, and United States v. Spaulding, 293 U. S. 498, 55 S. Ct. 273, 79 L. Ed. 617, we think the evidence was insufficient to sustain the verdict and judgment for the appellee and that the motion for a directed verdict should have been allowed.
The judgment of the court below is reversed.

Question: This question concerns the first listed appellant. The nature of this litigant falls into the category "federal government (including DC)", specifically "other, not listed, not able to classify". Which specific federal government agency best describes this litigant?

Choices:
United States - in corporate capacity (i.e., as representative of "the people") - in criminal cases
United States - in corporate capacity - civil cases
special wartime agency
Other unlisted federal agency (includes the President of the US)
Unclear or nature not ascertainable

Answer: 0