The Court first noted the problems with dictionary definitions in ascertaining the intent of drafters since they usually give a range of "linguistic possibilities," but "rarely do they help a court decide which one the drafter of the contract or statute in question intended." Here it was even worse, as the court picked a definition which Judge Posner finds it clear that the contract actually precluded.
Business firms almost always reserve the right to fire an employee (unless the employee is protected by a collective bargaining agreement) if the firm decides that the employee's performance is unsatisfactory. But it is precisely because of the insecurity of such employment -- the determination that Joy's performance was unsatisfactory was based on a criterion selected by the firm after she went to work for it, rather than being specified in her employment contract -- that employment contracts often provide for severance pay. Joy was leaving a good job to go to work for HGI and in doing so may have been taking a risk (though, with her mentor leaving Hewitt, maybe there would have been a risk in her remaining there), especially since she was going to be working in what was a new line of business for HGI. If she lost her job she would need money to tide her over while she looked for a new job. Hence the severance-pay provision in her employment contract with HGI.
The precise meaning that the word bears in the contract cannot be determined just from reading the contract, as HGI argues. It is a considerable irony that a firm that is in the business of consulting on executive compensation failed to draft a contract that clearly specified the compensation rights of one of its own executives.
Although that is the important part for Ms. Joy, Judge Posner is not through educating, noting the different circumstances where evidence might be allowable to determine the meaning of "cause" in this contract. Even if the meaning of the contract had been clear on its face, that did not necessarily mean all extrinsic evidence is excluded:
Extrinsic evidence, which is to say evidence besides just the written contract itself, is admissible to demonstrate that the contract may not mean what it says, provided the evidence used to show this is "objective" in the sense of not being merely self-serving, unverifiable testimony.