1. Whether illicit or innocent, the use of secure texting apps is probably here to stay.

2. An infrared camera can scan for people guarding illicit marijuana operations on nearby lands.

3. To date, the sum total of their illicit behavior was strictly small-time.

4. In some instances, cooperation involves the illicit exchange of cash.

5. In many cases, that legal traffic morphed into massive illicit immigration.

6. The Silk Road, an online marketplace of mostly illicit goods, only accepts bitcoin.