"It often makes you 'joint and severally liable' for any problem, " says Carlton Smith of Cardozo Law School in New York.

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He said it was his case that Mr Noble or Mr Lawless or Mr Gibbs "jointly and severally caused the death" of Mr Lavelle.

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Entrepreneurship will be severally hampered in both human and financial terms.

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But if the couple files a joint income tax return, then each of them will be jointly and severally liable for the income tax reported, or properly reportable, on the joint return.

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