The Supreme Court continues to hold a historic session on the constitutionality of the Affordable Care Act for the third and final day. On Tuesday, justices heard arguments over an issue at the heart of the healthcare law, the individual mandate requiring most people buy health insurance by 2014 or pay a tax penalty.

Details continue to emerge on the killing of the 17-year-old Florida teenager Trayvon Martin. According to ABC News, the lead homicide investigator at the crime scene called for manslaughter charges against Martin’s shooter, George Zimmerman, on the night of the shooting. In an affidavit, the investigator, Chris Serino, said he had doubts about Zimmerman’s account. Serino was overruled by the state attorney’s office, which accepted Zimmerman’s claim of self-defense.

On Tuesday, Trayvon Martin’s parents, Sybrina Fulton and Tracy Martin, testified before a House panel on hate crimes and racial profiling.

Sybrina Fulton: “Trayvon was our son, but Trayvon is your son. A lot of people can relate to our situation, and it breaks their heart, just like it breaks mine. Thank you for everything.”

Tracy Martin: “I would like to say thank you to everyone who is supportive of our family, everyone who has helped us stand tall in this matter, everyone who’s holding the legacy of Trayvon and making sure that he did not indeed die in vain. I’d just like to say thank you, and he’s sadly missed, and we will continue to fight for justice for him.”

Also speaking at the hearing were Congress Members Cedric Richmond of Louisiana and Frederica Wilson, who represents the Florida district where Trayvon Martin lived.

Rep. Cedric Richmond: “I, as a member of Congress, I, as a black male who wear a hoodie, I, as a black male who buy Skittles and walk down the street drinking iced tea all the time, I am Trayvon Martin.”

Rep. Frederica Wilson: “This investigation is laced with racial profiling, lies and murder. Trayvon was hunted, chased, tackled and shot. Ill-conceived laws and lax gun laws all contribute to this tragedy. In closing, Mr. Zimmerman should be arrested immediately for his own safety.”

In the New York legislature, a number of legislators wore hoodies in session, including New York State Senator Eric Adams, a former New York City police officer.

The Environmental Protection Agency has proposed the first-ever limits on greenhouse gas emissions from new power plants. Under the rule, new power plants would be required to keep emissions under 1,000 pounds of carbon dioxide for every megawatt hour of electricity. While Republicans are vowing to fight the measure for going too far, some environmental groups have criticized the Obama administration for exempting existing plants as well as allowing a number of loopholes. The rule exempts pollution from burning biomass and also grants waivers to plants that use carbon capture and storage technology, whose efficiency is under dispute. In a statement, Greenpeace USA called the new rules “welcome, but disappointing.”

More than a dozen Afghan soldiers have been arrested on suspicion of plotting a major attack inside the Afghan Defense Ministry in Kabul. The Defense Ministry was placed under lockdown on Tuesday after suicide vests were found inside its fortified compound. The arrests follow a spate of attacks by Afghan soldiers against members of the U.S.-led NATO occupation force. Afghan troops have been responsible for one-third of all U.S. troop deaths in Afghanistan this year.

The former head of Poland’s intelligence service has been charged with helping the CIA establish a secret prison as part of the Bush administration’s so-called war on terror. Zbigniew Siemiatkowski is accused of violating international law by “unlawfully depriving prisoners of their liberty” for his alleged role in helping the CIA set up a secret prison where torture was used. The charges mark the first high-profile case where a former senior official of any government has been prosecuted for the CIA program.

Fighting continues in Syria despite President Bashar al-Assad’s public acceptance of a U.N.-brokered ceasefire plan. The Syrian Observatory for Human Rights says 31 people, including 18 civilians, were killed in nationwide clashes on Tuesday. Thirteen soldiers were also reportedly killed. At the U.N., Middle East envoy Robert Serry said up to 9,000 people have been killed in the year-long Syrian crackdown.

Robert Serry: “Violence on the ground has continued unabated, resulting in scores of people killed and injured. Credible estimates put the total death toll since the beginning of the uprising one year ago to more than 9,000. It is urgent to stop the fighting and prevent a further violent escalation of the conflict. Immediate steps are needed now from the Syrian government to act on their commitments and demonstrate to the Syrian people that they are ready for a cessation of violence and a political process, issues on which the joint special envoy will also engage the opposition.”

A major gas leak on an offshore platform in the North Sea near Scotland has spurred widespread evacuations amid fears of an explosion. The French energy company Total, which operates the platform, said it could take up to six months to stop the flow of gas.

Scientists are warning the world is on the verge of reaching critical thresholds where damage from global warming will become irreversible. One scientist called this “the critical decade” for curbing global warming, saying the tipping point for irreversible damage to polar ice sheets has probably already been passed. Research shows the world’s temperature could rise by six degrees Celsius by the end of the century if greenhouse gas emissions continue to escalate.

The Arizona State Senate has voted to ban most abortions after 20 weeks of pregnancy. The vote was 20 to 10, with one Republican joining Democrats in opposition. The measure now goes to Arizona’s State House. Six states have passed similar abortion bans over the past two years.

Seven members of a Christian militia in the Midwest have been acquitted on charges of sedition and conspiracy. The accused, part of a group called the Hutaree, were arrested two years ago for an alleged plot to spark a war against the federal government by planning to kill a law enforcement officer and then bomb the funeral procession. But on Tuesday, a federal judge in Michigan ruled the defendants’ actions were protected by First Amendment rights to free speech. Two members of the militia still face less severe charges of possession of illegal weapons.

Supporters of the jailed environmental activist Tim DeChristopher are raising new concern about his treatment behind bars. DeChristopher is currently serving a two-year sentence for posing as a bidder to prevent oil and gas drilling on thousands of acres of public land. According to his legal defense fund, DeChristopher was recently removed from a minimum security prison ward into an isolated cell known as a “Special Housing Unit,” or SHU. He reportedly shares the tiny cell with another prisoner and has been allowed outside of it just four times over a two-week period. DeChristopher’s freedom to read books, write in his journal, and communicate with the outside world have all come under new restrictions.

A federal judge has barred the importation of a drug used in executions of death row prisoners. On Tuesday, Judge Richard Leon of the Federal District Court in Washington ruled the Federal Drug Administration had unlawfully allowed sodium thiopental into the United States. The case was brought on behalf of death row prisoners in Arizona, California and Tennessee. In his ruling, Judge Leon chided the FDA for what he called “a callous indifference to the health consequences of those imminently facing the executioner’s needle.”

Republican hopeful Newt Gingrich has announced he is scaling back his campaign, cutting back on appearances and laying off one-third of his staff. Gingrich has suffered a string of losses in recent primaries and has faced Republican calls to drop out of the race.

Amnesty International is accusing the U.S. government of systemic discrimination against Hispanics and Native Americans along the U.S.-Mexico border. In a new report, Amnesty says federal immigration programs operated with state and local police put “communities of color along the border at risk of discriminatory profiling.” The report also finds indigenous communities along the border are “often intimidated and harassed by border officials for speaking little English or Spanish and holding only tribal identification documents.” Amnesty says harsh policing is indirectly jeopardizing migrants’ right to life, forcing them to trek through treacherous terrain that led to more than 5,200 deaths from 1998 to 2008. Amnesty is calling on the U.S. to suspend immigration enforcement programs pending a review.

A JetBlue plane was forced to make an emergency landing in Texas on Tuesday after its captain apparently suffered a mental breakdown and accosted passengers on board. According to reports, the pilot emerged from the cockpit ranting about threats from Iraq, Iran and Afghanistan as well as urging passengers to recite the Lord’s Prayer as he marched through the cabin. Four passengers restrained him while a co-pilot and another pilot who happened to be on board landed the plane.

The American Civil Liberties Union has released records showing the FBI’s San Francisco division collected information on Muslim religious activities protected by the Constitution. The FBI is banned by law from keeping records on people’s religious practices unless there is a clear law enforcement purpose. But the ACLU said documents show the FBI violated that law and secretly stored records on Muslim religious groups.

And members of a food cooperative in Brooklyn, New York, have rejected a proposal to hold a referendum on boycotting goods from Israel. The Park Slope Food Coop had drawn international attention for its debate on whether to join the Boycott, Divestment and Sanctions campaign, or BDS, demanding Israel end the occupation of Palestinian land and grant Palestinian citizens equal rights. At a general meeting Tuesday night, Coop members defeated the proposal by a vote of 1,005 to 653. In a statement, organizers behind the BDS call at the Coop said: “Despite our loss, we have succeeded in one of our goals. BDS has entered into the consciousness of thousands of Coop members and has even made it into mainstream conversations thanks to the huge amount of media coverage.”