Who do I believe? Neighbor or Tenant

[Brian Horwitz]

Hi everyone, I received a note in the mail from an unknown neighbor at one of my rental properties (SFH) that read : "your rental property has very heavy drug activity going on at all hours of the night and day and loud music. the police will be notified along with child protection agency in regards to their 3 children. please address the problem asap"

I went by the place 3 times at night since I got the letter and didn't hear any music and I didn't see one person stop in. The Tenant (Husband, Wife, 3 kids) moved in about 6 months ago. They seem to be normal. Both work regular full time jobs. I contacted the wife and she said the crazy neighbor wrote the letter and none of it is true. The rental property is in C neighborhood. not terrible but not great either. Does anyone have experience with this? What do I need to do to make sure I'm not liable for not taking action?

Thanks!

Brian