Kyle Rodriguez died after voluntarily using heroin. The government proved to a
jury he bought it from Petitioner Maxwell Gaffney. The Government also proved
that this heroin use was the "but-for cause" of his death. However, there was a
multitude of intervening factors (alcohol, tolerance, use of suboxone, induced
vomiting) and other potential sources of drugs supplied to Kyle (ignored by the
prosecution), which the jury was not allowed to specifically address. This was
because, relying on Ninth Circuit precedent, the District Court declined to give an
instruction on proximate causation.

The question thus posed, which was deferred in Burrage v. United States, 571
U.S. 204 (2014) is whether the enhanced penalty provision of 21 U.S.C.
§841(b)(1)(C) requires a showing of proximate causation and therefore the jury
should be so instructed.

Whether the enhanced penalty provision of 21 U.S.C. §841(b)(1)(C) requires a showing of proximate causation