Yes, this is a scam.  I received a call this morning on my cell and business line from a guy stating he was from the Civil Liberties Division and there was a subpoena for me at my address.  I kept saying who? What? He wanted to transfer me to another number but after questioning him and asking his name, he hung up.  A few minutes later he called on my business line.  Here's what I did to fix them.  I sent them a text to a number they called from saying  the following.

Dear Caller,
You have reached the State Government office. Your number has been reported to our financial regulations office for repeatedly contacting consumers after you advised not to.  Once again we are advising you accordingly to the FCRA laws that govern this state to CEASE and Desist from contacting law abiding consumers with your scam.  Your telephone number is now on the FBI & all financial regulations offices in the nation alerting consumers of your scam.  Please be advised that if you do not adhere to these warning, the state of Texas as well as other regulatory offices will prosecute you and all parties involved to the full extent of the law. CEASE & DESIST NOW!!.