It's been a rough first four games for NFC West teams in the penalty department, and not just in the tripping department.
Officials have flagged teams from the division 153 times, assessing penalties covering 1,054 yards. The other divisions average 118 penalties and 835 penalty yards, according to ESPN Stats & Information. No division has as many in either category.
The totals count declined penalties.
2011 NFC West Penalty Ranks: Weeks 1-4
The chart below shows all 14 NFL players with at least five declined and assessed penalties this season. Five of them play for NFC West teams.
On a side note, penalties for unnecessary roughness are on the rise, with 57 having been called through the first four weeks of the season. There were 25 through the first four games of the 2007 season. That number has risen to 37 (2008), 41 (2009), 53 (2010) and now 57.
I doubt players have gotten any rougher unnecessarily. Officials are likely calling these penalties more aggressively. Calls for unsportsmanlike conduct are also up. There have been 17 through four games this season, up from an average of nine at this point in the previous four seasons.