This comes up as an "entertainment" question because you included the word "entertain" in the headline and it's clearly not an entertainment law question.
Regarding your unemployment claim, your clapping could be considered active participation, to the extent that it encouraged the actual perpetrator. That's more than not reporting the incident.
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Mr. Lynch is right. You can be fired for any reason. Definitely for not reporting an incident and clapping (cheering someone on). You are definitely in the need of an employment attorney.
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If you were terminated for failing to report the incident, then your employer has an argument for misconduct. Misconduct is grounds for terminating an employee. More importantly, TX is an at will state and allows employer to terminate you for good cause. By clapping, the employer can argue that you failed to take the required steps to report this incident; and thus, misconduct connected with the work.
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