Allstate ranks as the worst insurer for consumers, according to a comprehensive investigation of thousands of legal documents and financial filings by the American Association for Justice, a trial lawyers' group.

The group said it based its rankings on what it found to be "a distinct pattern of insurance industry greed" among 10 companies that do everything possible to avoid paying claims, employ hardball tactics against policyholders, reward executives with extravagant salaries, and raise premiums to maximize profits.

"While Allstate publicly touts its 'good hands' approach, it has instead privately instructed its agents to employ a 'boxing gloves' strategy against its policyholders," said American Association for Justice CEO Jon Haber. "Allstate ducks, bobs and weaves to avoid paying claims to increase its profits."

AAJ says Allstate is pretty much in a class by itself when it comes avoiding claims.

The group says the company contracted with consulting giant McKinsey & Co. in the mid-1990s to systematically force consumers to accept lowball claims or face its "boxing gloves," an aggressive strategy designed to deny claims at any cost.

AAJ says its charges against AllState are backed by thousands of court documents, materials uncovered from litigation and discovery, testimony, complaints filed with state insurance departments, SEC and FBI records, and news accounts.

The rest of the rankings are as follows:

2. Unum AAL takes this company to task for its actions in servicing its disability insurance products. AAJ says Unum's behavior was epitomized when it denied the claim of a woman with multiple sclerosis for three years, stating her conditions were "self-reported," contrary to doctors' evaluations. In 2005, Unum agreed to a settlement with insurance commissioners from 48 states over their practices.

3. AIG The world's biggest insurer, AIG's slogan was "we know money." In 2006, the company paid $1.6 billion to settle a host of charges.

4. State Farm State Farm fought hard to deny many claims along the Gulf Coast after Hurricane Katrina, AAJ says. The group says the company employed multiple engineering firms until they could deny the claims of one particular family in Mississippi. In April 2007, State Farm agreed to re-evaluate more than 3,000 Hurricane Katrina claims.

5. Conseco Conseco sells long-term care policies, typically to the elderly. Amongst its egregious behavior, the insurer "made it so hard to make a claim that people either died or gave up," according to a former Conseco subsidiary agent.

6. WellPoint Health insurer WellPoint has a long history of putting profits ahead of policyholders, AAJ said. The group says California fined a WellPoint subsidiary in March 2007 after an investigation revealed that the insurer routinely canceled policies of pregnant women and chronically ill patients.

7. Farmers Swiss-owned Farmers Insurance Group consistently ranks at or near the bottom of homeowner satisfaction surveys, according to AAJ.

8. UnitedHealth AAJ says physicians have complained that their reimbursements are so low and delayed by the company that patient health is being compromised.

9. Torchmark AAJ claims Torchmark has preyed on low-income Southern residents and charged minority policyholders more than whites for burial policies.

10. Liberty Mutual Like Allstate and State Farm, Liberty Mutual hired consulting giant McKinsey to adopt what AAJ calls "aggressive tactics." The group says Liberty's tactics were highlighted when a New York couple's insurance was "nonrenewed" by Liberty, even though they lived 12 miles from the coast and never experienced weather-related flooding.