What you have is a civil demand letter. If you strip away the fancy letterhead, law firm name, and legal language, what they are essentially asking you to do is to voluntarily pay a bunch of money they believe you owe them as a result of your shoplifting. There is a big industry of lawyers who specialize in sending these letters to people who have been caught shoplifting. The lawyers hope that enough of these people are scared into paying the amount asked that the lawyers make money.
I always advise my clients (this advice seems to be what many Avvo lawyers advise as well) to ignore the letter. The letter is voluntarily asking you to pay. Only a court of law can order you to pay. It is highly unlikely that you would be taken to court over such a small amount (~$100) of shoplifted merchandise. The court costs and legal fees alone would be tremendous. The law firm would also bear the burden of proof as to why they are entitled to the $375 they are seeking since you only took $100ish worth of stuff. In other words, the court will make the law firm prove where the extra $275 comes from.
Below is a link from the Wall Street Journal (February 2008 or so) detailing this industry of sending civil demand letters. Neal Tenen is quoted as being a leader or founder of the industry.
Hope that helps.
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