Here is some direction on what to do about negative Google Reviews:
1) “Flag as inappropriate”
Below every review on Google+ Local pages, you can click the flag icon:
2) Respond to the review
In addition to the flag icon, if you’re the owner of the page, you should also have the option to “Respond” to each review:
Not a ‘removal’ technique per se, but do this just in case the review isn't removed straight away but seen by others in the meantime.
3) Report the Google+ user profile
You could do this, but in this case, I do not think this is the right direction to “Report / block” the user as well. This can be done by navigating to the person’s G+ profile and clicking on the “Report / block [name]” link found below their avatar:
4) Report legal action
You’ll see this is Step 1.
When you go the “flag as inappropriate” route, there’s a box that says:
If you have located one or more reviews that you believe warrant removal from Google’s services based on applicable laws, please follow the instructions detailed on this page to submit a legal request.
That link lets you “Report other legal removal issue” depending on your country and its laws. You have to give a bit of info (the content and its URL, plus why you think it breaks the law), leave a “digital signature” and tick a box that means you “swear, under penalty of perjury, that the information in this notification is accurate and that [you are] authorised to report this alleged violation.” Pretty serious stuff.
