WASHINGTON -- The Supreme Court on Tuesday agreed to hear a challenge to federal campaign contribution limits and issued decisions concerning a drug-sniffing dog, an international child-custody dispute and when the police may detain people while conducting a search.
Campaign Finance In what may turn out to be the most important federal campaign finance case since the 2010 decision in Citizens United, the court agreed to decide whether aggregate limits on federal campaign contributions are constitutional.
The case was brought by Shaun McCutcheon, an Alabama man, and the Republican National Committee. Mr. McCutcheon said he was prepared to abide by contribution limits to individual candidates and groups, which are currently $2,500 per election to federal candidates; $30,800 per year to national party committees; $10,000 per year to state party committees; and $5,000 per year to other political committees.
But Mr. McCutcheon said he objected to separate overall two-year limits, currently $46,200 for contributions to candidates and $70,800 for contributions to groups, arguing that they were unjustified and too low.
He said that he had made contributions to 16 federal candidates in recent elections and that he wanted to give money to 12 more. He also said he wanted to give $25,000 to each of three political committees of the Republican Party. Each set of contributions would have put him over the overall limits.
In September, a special three-judge Federal District Court in Washington upheld the overall limits, saying they were justified by the need to prevent circumvention of the basic limits. The court relied on the Supreme Court's 1976 decision in Buckley v. Valeo, in which contributions were subject to a different analysis than expenditures (which were at issue in Citizen United).
The new case, McCutcheon v. Federal Election Commission, No. 12-536, may provide the Supreme Court with an occasion to revisit and perhaps revise that distinction.
Search Warrants In a 6-to-3 decision, the court ruled that the police may not stop and detain people without probable cause in connection with a search warrant authorizing the search of a place once they had left the premises.
The case, Bailey v. United States, 11-770, concerned Chunon Bailey, a New York man who left an apartment in 2005 as it was about to be searched. The police had a warrant to look for a gun, which they ultimately found. They also followed Mr. Bailey's car for about a mile before stopping, handcuffing and searching him.
Mr. Bailey was later convicted of gun and drug charges. He asked the trial judge to suppress evidence from the stop -- statements he made and a key linking him to the apartment -- but lower courts refused, relying on Michigan v. Summers, a 1981 Supreme Court decision allowing the detention of people in the immediate vicinity of the place to be searched.
Justice Anthony M. Kennedy, writing for the majority, said none of the interests justifying detention of people at the scene had allowed Mr. Bailey to be detained. People far from the scene are not able to endanger officers conducting the search or to disrupt it, he said. Nor could the interest in "preventing flight" be stretched, he wrote, to "justify, for instance, detaining a suspect who is 10 miles away, ready to board a plane."
Justice Kennedy added that a detention in public gives rise to a different sort of indignity than one inside a home.
Chief Justice John G. Roberts Jr. and Justices Antonin Scalia, Ruth Bader Ginsburg, Sonia Sotomayor and Elena Kagan joined the majority opinion.
In a dissent, Justice Stephen G. Breyer, joined by Justices Clarence Thomas and Samuel A. Alito Jr., said the police had acted sensibly in waiting to stop Mr. Bailey and that his detention was justified.
"I believe," Justice Breyer wrote, "that the majority has substituted a line based on indeterminate geography for a line based on realistic considerations related to basic Fourth Amendment concerns such as privacy, safety, evidence destruction and flight."
Police Dogs In a unanimous decision, the court decided the first of two cases concerning sniffing dogs on its docket this term, Florida v. Harris, No. 11-817.
The case concerned Clayton Harris, who was pulled over in 2006 near Bristol, Fla., for driving with an expired license plate. A police dog named Aldo alerted his human partner to contraband in Mr. Harris's pickup truck.
Based on the alert, the officer searched the truck and found, Justice Kagan wrote for the court, "200 loose pseudoephedrine pills, 8,000 matches, a bottle of hydrochloric acid, two containers of antifreeze and a coffee filter full of iodine crystals -- all ingredients for making methamphetamine."
The Florida Supreme Court suppressed the evidence, saying that prosecutors had not adequately established the reliability of Aldo's nose through comprehensive documentation of his performance in earlier searches. Justice Kagan said the dog's substantial training and certification sufficed.
"The question -- similar to every inquiry into probable cause -- is whether all the facts surrounding a dog's alert, viewed through the lens of common sense, would make a reasonably prudent person think that a search would reveal contraband or evidence of a crime," she wrote. "A sniff is up to snuff when it meets that test. And here, Aldo's did."
The case was argued in October on the same day as Florida v. Jardines, No. 11-564, concerning a sniffing dog outside a home, and there was reason to think the two cases would have been decided together. But the justices apparently found the question in the second case harder.
Child Custody The court unanimously ruled that Jeffrey L. Chafin, an Army sergeant and an American, should have been allowed to appeal a decision against him in an international child-custody dispute with his ex-wife, Lynne H. Chafin, a British citizen. The couple had a daughter in 2007 while Sergeant Chafin was stationed in Germany. Later that year, Ms. Chafin and their daughter moved to Scotland while Sergeant Chafin was deployed to Afghanistan.
Shortly after the family was reunited in 2010 in Alabama, Sergeant Chafin sought a divorce in state court and asked for custody. Ms. Chafin, for her part, asked a federal judge in Huntsville to allow her to take her daughter to Scotland under The Hague Convention, which requires courts to make sure that custody decisions are made in the country of the child's "habitual residence."
She won and left the country with her daughter almost immediately. The federal appeals court in Atlanta dismissed Sergeant Chafin's appeal as moot.
Chief Justice Roberts, writing for the court in Chafin v. Chafin, No. 11-1347, said that ruling was a mistake. "No law of physics prevents" the girl's "return from Scotland," he wrote, and Ms. Chafin might decide to comply with an American court order even if she does not have to under Scottish law.
Moreover, the chief justice wrote, the trial court had ordered Sergeant Chafin to pay more than $94,000 in court and lawyers fees and in travel expenses. The prospect of getting the money back also meant the case was not moot, he wrote.
This article originally appeared in The New York Times.