According to the IRS your fee received for witness is reported as Non Employee Compensation.
You do not necessarily have to "have a business," but simply perform services as a nonemployee to have your compensation treated this way. The payer has determined that an employer-employee relationship does not exist in your case.
Here is a link to the IRS Instructions for 1099MISC
I sincerely XXXXX XXXXX information is helpful,
The Self Employment tax will be required on this income you received for the witness. This is unfortunate since you were basically "forced" to do what you did to receive the money.
I truly wish I could advise other,
I have placed a link to the instructions for 1099MISC Box 7