BP shareholders are fleeing the company’s stock amid growing uncertainty about the ultimate bill for cleanup costs, lawsuits, fines and damage to the oil giant’s reputation.

BP’s shares fell an additional 15 percent on Tuesday, as investors reacted to news that the latest effort to stem the gushing oil in the Gulf of Mexico failed over the weekend. It is the steepest drop in shares in about two decades.

Also on Tuesday, Attorney General Eric H. Holder Jr. said that federal authorities had opened criminal and civil investigations into the Deepwater Horizon explosion.

Since the Deepwater Horizon drilling rig exploded April 20, the company has lost a third of its market value, or about $75 billion.

The company said Tuesday that it had spent almost $1 billion on cleanup efforts. But that bill is likely to rise as oil continues to spill into the gulf, with no guarantees that any of the new plans to contain the spill will work.

Investors are also grappling with potential damage to the company’s reputation.

“Financially they can survive this crisis, but politically they will be punished for a very long time,” said Fadel Gheit, an oil analyst at Oppenheimer & Company.

The prospect of billions of dollars more in legal payouts and fines is also weighing on the company.

BP officials say they have already paid $36 million to settle claims of economic loss and damage under the Oil Pollution Act, a 1990 law passed in the wake of the Exxon Valdez disaster, and that more than 26,000 claims have been submitted.

A Massachusetts state senator caught on video stuffing what prosecutors said was bribe money into her sweater and bra has pleaded guilty to corruption charges.

Dianne Wilkerson, a Boston Democrat, entered the pleas to eight counts of attempted extortion at a hearing in U.S. District Court on Thursday. She will remain free on bail until her sentencing on Sept. 20.

Federal prosecutors are recommending a sentence of no more than four years in prison. Defense attorneys will be allowed to argue for less.

Wilkerson was arrested in October 2008 and accused of taking $23,500 in bribes to help get a liquor license for a nightclub and helping an undercover agent posing as a businessman who wanted to develop state property.

The last of seven New York teenagers implicated in the hate crime killing of an Ecuadorean immigrant pleaded guilty on Wednesday.

Anthony Hartford's plea to gang assault and other charges closes the prosecution phase of a case that attracted international headlines and prompted an ongoing U.S. Justice Department probe of police responses to bias crimes. The judge indicated Hartford would likely face 10 years in prison when he is sentenced on July 20.

The 18-year-old admitted being with a group that targeted Hispanics for violence in November 2008. Their attacks culminated in the killing of immigrant Marcelo Lucero in Patchogue.

"He's never denied being involved," said defense attorney Laurence Silverman. "He's never denied that it was wrong to be involved."

A week ago, 19-year-old Jeffrey Conroy was sentenced to 25 years in prison for his conviction on manslaughter as a hate crime. Five others are awaiting sentencing.

A jury sentenced a 28-year-old Nevada man to death for raping and killing a college coed after sexually assaulting two others in Reno more than two years ago.

The same Washoe County District Court jury that convicted James Biela (BEEL'-uh) last week deliberated about nine hours before reaching a unanimous verdict Wednesday.

The former pipe fitter from Sparks will be sent to death row to await execution by lethal injection.

Biela's public defenders asked the jury to spare Biela's life because he had no previous criminal record and had been abused growing up in poverty in the Chicago area.

Nineteen-year-old Brianna Denison was raped and strangled to death during a string of attacks that shook the Reno community in early 2008.

• Drunk Driving (DUII, DUI, DWI) - including underage drinking and driving, refusing a breathalyzer test, driving under the influence of drugs or alcohol, and other drug or alcohol related driving offenses
• Criminal Driving Offenses - including manslaughter, criminally negligent homicide, assault, hit & run, attempting to elude police, reckless driving and licensure issues
• Drug Crimes - including possession
  
  , delivery, and manufacturing of marijuana, cocaine, methamphetamine, heroin, designer drugs and prescription drugs
• Property Crimes - including theft, embezzlement, forgery, fraud, computer crimes and burglary
• Violent Crimes - including menacing, stalking and assault
• Stalking - including criminal offenses and civil actions

A Chicago lawyer was found guilty Wednesday of conspiracy to commit tax fraud in connection with the sale of tax shelters.

A New York jury also convicted John Ohle III, 42, of two counts of tax evasion for failing to report about $6.5 million in income in 2001 and 2002, the U.S. attorney's office in Manhattan said Thursday. A fellow lawyer, William Bradley of Hammond, La., also was convicted in the conspiracy scheme.

The guilty verdicts are a big victory for New York federal prosecutors who have investigated a web of Chicago lawyers, bankers and accountants who helped hundreds of wealthy clients skirt taxes through the sale of questionable tax shelters starting in the 1990s. Last year, seven people, including the former chief executive of BDO Seidman, a Chicago-based accounting firm, were charged with fraud and conspiracy related to the sale of allegedly fraudulent tax shelters.

One of the shelters was known as "Hedge Option Monetization of Economic Remainder" or "HOMER." The U.S. attorney's office said Ohle sold HOMER to clients of Bank One, where he was employed from November 1999 to early 2002. Ohle continued selling the shelter after leaving the bank and forming his own company, Chicago-based Dumaine Group LLC.

Prosecutors had alleged that Ohle and Bradley conspired with others to create fraudulent invoices to obtain referral fees on transactions involving HOMER. Ohle illegally collected more than $800,000, prosecutors said.