A Massachusetts man accused of killing his wife, two children and mother-in-law pleaded not guilty Thursday to four counts of first-degree murder as a prosecutor described how he left two copies of a letter confessing to the slayings.

Thomas Mortimer IV was arraigned in Woburn Superior Court on Thursday following his indictment last week. He had previously entered not guilty pleas in district court and has been held without bail since his arrest following the killings in June.

Mortimer frowned as he listened to a clerk read an indictment charging him in the murders of his wife, 41-year-old Laura Stone Mortimer, mother-in-law, 64-year-old Ellen Stone, and two children, 4-year-old Thomas Mortimer V, and 2-year-old Charlotte Mortimer. He did not look at his wife's family members, seated in the front row of the courtroom.

The family was found beaten and stabbed to death in their Winchester home.

District Attorney Gerard Leone has said that the slayings followed a fight and "ongoing marital discord." Leone said there were signs that Mortimer attempted suicide at the home.

The revelation that BP's Texas City refinery emitted toxic benzene for more than a month has ignited a furor in the port community that has suffered its share of deadly industrial accidents and toxic spills.

Thousands of residents who fear they may have been exposed to the known carcinogen released at the oil refinery from April 6 to May 16 have been flooding parking lots and conference halls where local trial attorneys hosted information sessions and sought clients for class-action lawsuits against the oil giant.

BP faces the new challenge just as it is reaching a key milestone in another crisis — plugging the Gulf of Mexico well that blew out in an oil spill disaster that is costing the company billions of dollars.

On Wednesday, more than 3,400 people lined the hallways and sidewalks around the Nessler Center to sign on to a $10 billion class-action lawsuit filed Tuesday in Galveston federal court by Friendswood attorney Anthony Buzbee.

The lawsuit alleges the release of 500,000 pounds of chemicals - including 17,000 pounds of benzene - has jeopardized the health and property values of people who live and work in the area. At the nearby College of the Mainland, a separate town hall meeting drew a crowd of 600.

The doctor charged in Michael Jackson's death is due back in court for a scheduling hearing that will determine when prosecutors will publicly present some of their evidence.

Dr. Conrad Murray is required to attend Monday's hearing, during which a Los Angeles judge is expected to schedule a preliminary hearing for later this year.

The judge will decide at that hearing whether there is enough evidence for the involuntary manslaughter case against the cardiologist to continue. Murray, who maintains offices in Las Vegas and Houston, was charged in February for administering a lethal dose of anesthetic propofol to Jackson.

Murray has pleaded not guilty and his attorneys have said the physician did not give Jackson anything that "should have" killed him.

A $10 billion toxic tort class action lawsuit has been filed against BP over alleged emissions from its troubled Texas City oil refinery, alleging that workers and residents in the area were exposed to benzene and other chemicals.  

More than 2,200 workers at the refinery and residents from the surrounding area filed the BP class action lawsuit on August 3 in the Galveston Division of the Southern District of Texas. The complaint alleges that for 40 days earlier this year, the company illegally released the chemical benzene into the atmosphere.

The benzene lawsuit comes just as BP, formerly known as British Petroleum, was finally able to stop the flow of oil from a well a mile under the surface of the Gulf of Mexico, which has caused a massive oil spill that is expected to cost the company tens of billions of dollars in oil spill lawsuits and clean up costs.

Plaintiffs in the BP Texas City refinery class action lawsuit say the company has been releasing benzene into the atmosphere at the plant due to a hydrogen compressor that broke down on April 6. The 2,212 plaintiffs allege that they suffered serious injuries and illnesses from benzene exposure.

Benzene is an industrial chemical that has been linked to the development of cancer, leukemia and other life-threatening health problems. It is a known carcinogen used as an industrial solvent in the production of plastic and synthetic rubber, as well as drugs and dyes.

BP’s Texas City Refinery is the third-largest oil refinery in the United States, and has been the subject of several major safety incidents. As recently as September, the U.S. Occupational Safety and Health Administration hit BP with an $87.4 million fine for not complying with a safety agreement made after a March 23, 2005 explosion and fire that killed 15 workers and injured more than 170 others.

In February 2009, BP Products North America agreed to pay $180 million to resolve a separate environmental lawsuit over benzene emissions at the oil refinery. That case involved violations of a 2001 consent decree and Clean Air regulations which were identified during inspections by the U.S. Environmental Protection Agency (EPA) following the March 2005 blast.

California's high court on Monday upheld the state's 14-year-old law barring preferential treatment of women and minorities in public school admissions, government hiring and contracting.

In a 6-1 ruling, the state Supreme Court rejected arguments from the city of San Francisco and Attorney General Jerry Brown that the law, known as Proposition 209, violates federal equality protections.

Opponents of the ban say it creates barriers for minorities and women that don't exist for other groups, such as veterans seeking preference.

The ruling written by Justice Kathryn Werdegar came in response to lawsuits filed by white contractors challenging San Francisco's affirmative action program, which was suspended in 2003.

"As the court recognized, Proposition 209 is a civil rights measure that protects everyone, regardless of background," said Sharon Browne, a lawyer for the Pacific Legal Foundation, which represented the contractors. "Under Proposition 209, no one can be victimized by unfair government policies that discriminate or grant preferences based on sex or skin color."

If San Francisco wants to resurrect the program, the Supreme Court said it must show compelling evidence the city "purposefully or intentionally discriminated against" minority and women contractors and that such a law was the only way to fix the problem.