IN 2004, Arizona voters approved a measure demanding proof of citizenship from those who seek to register to vote in the state. On Monday, the Supreme Court ruled the measure invalid.

The court looked to the 1993 National Voter Registration Act, also known as the motor voter law, which was supposed to streamline voter registration across the country. Among other things, it empowered a commission to develop a common registration form that all states have to “accept and use” to populate federal election rolls. The resulting form requires a signed affirmation of citizenship but no supporting documents. Under its 2004 law, though, Arizona rejected completed federal forms without documentation.

IN RESPONSE to the outcry that followed Robert Ethan Saylor’s fatal encounter with off-duty deputies in Frederick County, Sheriff Charles A. Jenkins promised “that this agency is transparent and that all the facts will be presented when the investigations are completed.” But the public is still in the dark about how the refusal of this young man to leave a movie theater could end in his death. Now come troubling details about the department’s handling of another incident that also resulted in death. It’s enough to make one wonder who exactly is being protected in Frederick County and whether it’s time for an independent look by outside agencies. The circumstances of the two cases, occurring within days of each other in January, vary greatly, but each raises issues of whether these fatalities could have been avoided had authorities acted differently.

HASSAN ROUHANI will be Iran’s next president not only because he was picked by a majority of Iranian voters but also because the country’s supreme leader, Ayatollah Ali Khamenei, chose to accept his victory. That decision surprised us and some Western experts on Iran, but in retrospect there was good reason for it. Had the Islamic regime falsified the results and blocked Mr. Rouhani, it would have risked a repeat of the popular uprising that followed the 2009 election, when followers of reformist candidates concluded — probably rightly — that the reelection of hard-liner Mahmoud Ahmadinejad had been rigged.

IT’S WELL understood that if nuclear war ever comes, it is the president who has to make the fateful decisions. But if the United States ever faced a genuine conflict in cyberspace, with decisions having to be made at network speed against adversaries unknown or hard to find, who would be in charge? A major attempt to sort this out at the highest levels is evident in President Policy Directive 20, which President Obama signed last October. The directive is still classified as top secret but was among the papers spilled into public view by Edward Snowden, the contractor for the National Security Agency who also revealed classified materials on Internet and telephone surveillance.