When debt collectors engage in conduct prohibited by state and federal law, they can be sued in federal court under the Fair Debt Collection Practices Act (The FDCPA). They can also be sued under a state statute in California called the Rosenthal Act.
Some examples of actions debt collectors are specifically prohibited from taking include: threatening to sue you, garnish your wages, or have you arrested; contacting your family, friends, or employers to collect a debt; failing to tell you specific things they are required to tell you when they call you on the phone or send you a letter in an effort to collect a debt; insulting you, swearing at you, or leaving abusive phone messages; lying to you; contacting your place of work after you have told them not to do so; and many others.
If you have experienced any of the above situations, you may very well have a good case against a debt collector. Not only does bringing a law suit against an abusive debt collector help stop the harassment against you, it helps protect other consumers from suffering from similar treatment. Debt collectors who violate these laws and abuse consumers do so because doing so can be an effective way to get people to pay them. Unless their illegal conduct is met with consequences by way of a law suit that will cost them money, most abusive debt collectors will continue to harass consumers. When you sue a debt collector it tells them they cannot get away with violating the law and will cause them to think twice about abusing other consumers going forward.