Unanswered are questions about carrying firearms in public, gun sales on government property, firearm registration, guns in government housing, handgun restrictions that aren't exactly the same as the District of Columbia's, zoning and gun stores, and so on. And so far, at least, lower courts have been overwhelmingly hostile to gun owners' rights.
The latest example is a decision late Thursday by the U.S. Court of Appeals for the Tenth Circuit, which said that a criminal defendant may not be allowed to present a Second Amendment defense to a federal jury in Utah. It came after the appeals court granted an extraordinary emergency appeal, called a writ of mandamus, from the Justice Department after the district judge agreed to allow those jury instructions.
The defendant, Rick Engstrum, has an earlier misdemeanor domestic violence conviction and has been charged with possessing a firearm in violation of a federal law that applies to anyone "who has been convicted in any court of a misdemeanor crime of domestic violence." He has pleaded not guilty.
(The prosecution arose when Engstrum broke up with his girlfriend, who subsequently told police that he had a gun in his bedroom. Engstrum voluntarily showed police the gun, which he inherited from his father; there's no evidence he has ever used the firearm, let alone threatened anyone with it.)
Engstrum, reasonably, wanted to argue to the jury that the Second Amendment renders that law invalid, at least when applied to people who show no risk of future violence. (Remember, this is a Utah jury, which raises the odds that jurors are familiar with the right to keep and bear arms, and may even have heard of the concept of jury nullification.)
The Justice Department rejected this idea out of hand. By a 2-1 margin, a Tenth Circuit panel agreed, concluded that the Second Amendment didn't apply, and prohibited those jury instructions. "If the case proceeds to trial, the district court is directed not to instruct the jury on this Second Amendment defense, including not giving the proposed jury instruction," they wrote.
The two judges who slapped down the Second Amendment defense were both Republican appointees. Paul Kelly was a George H. W. Bush appointee, and Harris Hartz was a George W. Bush appointee.
More interesting is the dissent, written by Clinton appointee Michael Murphy. (An aside: Murphy spent much of his life in Wyoming and Utah, while his colleagues spent most of their careers in New Mexico.)
This court has not yet passed on the constitutionality of (the federal law dealing with domestic violence) in light of District of Columbia v. Heller. That opinion's recognition of an individual right to bear arms for the defense of self, family, and property, raises substantial questions about how (the law) may be constitutionally applied...
This case presents novel constitutional questions, and I would prefer further briefing before deciding them. I express no opinion on whether the district court's approach is correct, but I cannot conclude the government has met its heavy burden of showing that the district court, in light of virtually no guidance from this court or the Supreme Court, is so far afield that the government is clearly entitled to relief... I would grant a stay of the proceedings below and order further briefing on the constitutional question.
Unfortunately, last year's U.S. v. Heller doesn't provide much in the way of guidance to the lower courts. The majority opinion did say, without elaborating, that "nothing in our opinion should be taken to cast doubt on longstanding prohibitions on the possession of firearms by felons and the mentally ill, or laws forbidding the carrying of firearms in sensitive places such as schools and government buildings."
That was enough for a federal district judge in Maine, in U.S. v. Booker, to rule that the domestic violence prohibition was constitutional. (Plus, a 2009 Supreme Court decision raised no objections to the domestic violence statute, but without evaluating it in terms of the Second Amendment.)
Douglas Berman, a professor of law at Ohio State University's Moritz College of Law, said on Friday that the panel's decision "shows significant antipathy toward serious consideration of Second Amendment rights."
"Anyone seriously committed to the Second Amendment and gun rights getting serious constitutional respect should be seriously disturbed by how willing and eager lower courts have been to accept federal prosecutors arguments that Heller is of no consequence for an array of broad and severe federal gun possession crimes," Berman wrote.
The bottom line? Forget the rhetoric on both sides after last year's Heller decision. So far, at least, there seems to be few state or federal gun-related laws -- except, perhaps for a complete handgun ban -- that U.S. courts are willing to strike down as unconstitutional.
Declan McCullagh is a correspondent for CBSNews.com. He can be reached at email@example.com.