Some deleted comments should not be viewable

Our Jira installation is relatively open to the public (anyone can create an account, create issues and add comments). At times an account is created for nefarious (or at least obnoxious) purposes and comments are added to issues (probably buy a bot) with inappropriate content. As an administrator, I can relatively easily delete the comment. However, the redacted comment is still viewable under the "All" subtab, along side my name. Some users incorrectly interpret this and believe that my account was used to create the comment.

Additionally, these links are still accessible to web crawlers, so the spammers intent has not be thwarted by our removal of the comment - it only changed the location.

Perhaps deleted comments and the change log regarding them could only be viewed by administrators. Or maybe fully deleted. Regardless, we need these links permanently removed!