Question: Who argued that it may be impossible to impanel a jury in compliance with the Vicinage Clause of the Sixth Amendment for a crime committed solely in the unpopulated Idaho portion of Yellowstone National Park?
About the article "Yellowstone National Park", section "Legal jurisdiction".

Candidate passages:
The entire park is within the jurisdiction of the United States District Court for the District of Wyoming, making it the only federal court district that includes portions of more than one state (Idaho, Montana, and Wyoming).
Law professor Brian C. Kalt has argued that it may be impossible to impanel a jury in compliance with the Vicinage Clause of the Sixth Amendment for a crime committed solely in the unpopulated Idaho portion of the park (and that it would be difficult to do so for a crime committed solely in the lightly populated Montana portion).
One defendant accused of a wildlife-related crime in the Montana portion of the park attempted to raise this argument.
He eventually pleaded guilty.
The United States District Court for the District of Wyoming (in case citations, D.
Wyo.)
is the Federal district court whose jurisdiction comprises the state of Wyoming and those portions of Yellowstone National Park situated in Montana and Idaho.
The court has locations in Cheyenne and Casper.
Appeals from this court are heard by the United States Court of Appeals for the Tenth Circuit (except for patent claims and claims against the U.S. government under the Tucker Act, which are appealed to the Federal Circuit).
The United States Attorney's Office for the District of Wyoming represents the United States in civil and criminal litigation in the court.
The district of Wyoming is the only federal court district that includes portions of more than one state.
Law professor Brian C. Kalt has argued that it may be impossible to impanel a jury in compliance with the Vicinage Clause of the Sixth Amendment for a crime committed solely in the Idaho portion of the park (and that it would be difficult to do so for a crime committed solely in the Montana portion).  
The Vicinage Clause is a provision in the Sixth Amendment to the United States Constitution regulating the vicinity from which a jury pool may be selected.
The clause says that the accused shall be entitled to a jury "of the State and district wherein the crime shall have been committed, which district shall have been previously ascertained by law".
The Vicinage Clause limits the vicinity of criminal jury selection to both the state and the federal judicial district where the crime has been committed whereas the venue provision of Article Three of the United States Constitution regulates the location of the actual trial.
The Vicinage clause has its roots in medieval English criminal procedure, the perceived abuses of criminal vicinage and venue during the colonial period and Anti-federalist objections to the United States Constitution.
The clause is one of the few constitutional criminal procedure provisions that has not been incorporated to apply to proceedings in state courts, along with the Grand Jury Clause of the Fifth Amendment and (maybe) the Excessive Bail Clause of the Eighth Amendment.
The Clause has led to very little litigation, in part because of its overlap (as a practical matter) with the venue provision of Article Three and Rule 18 of the Federal Rules of Criminal Procedure.
Further, with the exception of the District of Wyoming, which includes the portions of Yellowstone National Park in Idaho and Montana "(see below)", no federal judicial district includes the territory of two or more states (although the short-lived District of Potomac once did). 
Professor Brian C. Kalt of Michigan State University College of Law argues that the Vicinage Clause may permit the commission of the "perfect crime" in the portion of Yellowstone National Park within the state of Idaho because the entire park is within the District of Wyoming and the Idaho portion of the park has no residents (and that a less perfect crime could be committed in the lightly populated Montana portion of the park).
Kalt argues that two arguments the government might make in favor of prosecution would be unsuccessful: that the Idaho portion of the park is not part of a state and that the judicial district could be changed after the crime.
However, Kalt argues that the Vicinage Clause might permit a variety of prosecutorial strategies that would at least partially close this loophole.
First, the government might be able to charge other crimes that did not occur exclusively within the Idaho portion of the park (for example, if the defendant(s) conspired elsewhere).
Second, the government could charge crimes for which the maximum authorized sentence is six months or less, to which the jury right does not attach.
Third, the Clause might permit the government to encourage potential jurors to move into the Idaho portion of the park after the crime.
Fourth, the government might argue for a purposive, rather than textualist, interpretation of the Clause by arguing that a jury drawn from elsewhere could satisfy the purposes of the Clause.
Kalt also notes that the Vicinage Clause would not protect against civil liability or vigilante justice.
This same problem also was cited by the Nevada Legislature as a reason to dissolve Bullfrog County, Nevada, a short-lived county specially created in 1987 for purposes of shifting federal transfer payments related to the creation of the Yucca Mountain nuclear waste facility directly to the state treasury. 
U.S. Const.
Art.
III, § 2, cl.
3 provides: Trial of all Crimes, except in Cases of Impeachment, shall be by Jury .
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U.S. Const.
amend.
VI provides: In all criminal prosecutions, the accused shall enjoy the right to a .
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trial, by an impartial jury of the State and district wherein the crime shall have been committed, which district shall have been previously ascertained by law .
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One of the enumerated complaints in the Declaration of Independence accused King George III of "depriving us, in many Cases, of the Benefits of Trial by Jury."
Availability Depending on the authorized and actual sentence, upon demand, a criminal defendant has a right to trial by jury.
The defendant does not have a right, conversely, to a bench trial without the consent of the prosecution.
If the defendant is charged with crimes for which the authorized sentence exceeds six months, whether in state or federal court, the defendant has a right to a jury.
Further, the defendant has a right to a trial by jury if the actual sentence exceeds six months and the charged crime has no maximum authorized sentence (e.g.
contempt of court).
But, the defendant does not have a right to a jury in stacked misdemeanor prosecutions, even if the cumulative authorized imprisonment exceeds six months, as long as the actual sentence does not.
Factors other than actual and authorized sentences may be relevant to seriousness, but so far the Court has pushed back against expanding the jury right.
Impartiality The trial judge has an obligation to ensure an impartial jury, especially vis-a-vis juror biases and media coverage by such means as jury selection (including voir dire and for-cause challenges), jury sequestration, and jury instructions.
For example, this may require the court to permit voir dire on the subject of the juror's potential racial prejudice.
In some circumstances, the Sixth Amendment even requires the trial judge to grant a defendant's change of venue motion if an impartial jury cannot be obtained otherwise.
The Sixth Amendment also regulates the availability and use of cause and peremptory challenges.
For example, it precludes a jurisdiction from granting the prosecution for-cause removal of jurors who oppose the death penalty.
"The most that can be demanded of a venireman in this regard is that he be willing to "consider" all of the penalties provided by state law, and that he not be irrevocably committed, before the trial has begun, to vote against the penalty of death regardless of the facts and circumstances that might emerge in the course of the proceedings."
While a defendant is not obliged to use peremptory challenges to cure a trial court's erroneous denial of a defendant's for-cause challenge, if the defendant does so, the defendant may not rely on the error for automatic reversal.
Size and unanimity The Supreme Court has held that six-member juries are sufficient and that five-member juries are not.
Verdict unanimity is not required for twelve-member juries, but is required for six-member juries.
Vicinage The provision requiring that the jury be drawn "of the State and district wherein the crime shall have been committed, which district shall have been previously ascertained by law" is known as the Vicinage Clause.
The Vicinage Clause places no limits on the prosecution of crimes not committed within a state.
Nor does the Clause prevent a crime from being tried by a jury from a different division (a subset of a federal judicial district) within the same district in which the crime was committed.
The Third, Fifth, and Sixth Circuits have held that the Vicinage Clause was not incorporated against the states by the Fourteenth Amendment.