Despite tracking tackles on NFL.com, the league actually doesn't consider tackles an official statistic. There's no oversight when they are accumulated, largely because the tackle is finalized during the moment that it happens. When Player A tackles someone for a two-yard gain, player A receives a tackling credit and the NFL moves on. Multiple players can take part on a tackle and fail to receive credit, largely because it's difficult to see without replay and would require additional viewings of a game just to get an accurate number.
That being said, Bengals linebacker Vontaze Burfict finished the season leading the NFL with 171 tackles - ten more tackles than second-place, Jaguars linebacker Paul Posluszny.
That's the NFL's number.
When Bengals assistants watch film from the previous game, they also record tackle numbers that are generally more accurate (due to re-watching the game). According to the Bengals, Burfict actually led the team with 204 tackles. Rey Maualuga, who finished second, generated 110 tackles, nearly 100 less than Burfict (though Maualuga did miss three games).
Burfict also finished the season first on the team with eight tackles-for-loss on rushing plays, third (and tied for first among the front seven) with 10 passes defensed, second with two fumble recoveries and added three quarterback sacks, a pick, and a fumble-six.
The second-year defensive leader became the first Bengals linebacker since Jim LeClair (1976) to be voted into the Pro Bowl this year.