Here's what we know about Hamilton 68, the Russian online influence tracker called into question by the 'Twitter Files'

• A recent "Twitter Files" drop revealed deep concerns among Twitter executives about a database that claimed to track Russian propaganda in "near real time."
• The now defunct database, Hamilton 68, was widely cited by media outlets, including Insider, before it was shut down in 2018.
• Conservatives have accused it of having a left-wing bias, while its creators say the dashboard's data was often misunderstood and misinterpreted.

Selectively leaked emails that appear to show internal discussions between Twitter executives have raised doubts about a prominent database used to track Russia's online influence campaigns.