A more thorough explanation:

An erroneous assessment is a determination of the rate or amount of something, such as a tax or damages, that deviates from the law and creates a jurisdictional defect, and that is therefore invalid. For example, if a tax assessor mistakenly values a property at a higher amount than it is worth, resulting in a higher tax bill for the property owner, it would be an erroneous assessment.

Another example of an erroneous assessment is when a tax is imposed twice for the same property, which is known as double assessment. This is not allowed and creates a jurisdictional defect, making the assessment invalid.

It is important for assessments to be accurate and in accordance with the law to avoid erroneous assessments and potential legal issues.