ALCS Game 2 (DET-BOS): The Non-Fan Interference Foul

Prince Fielder tangled with fans on a pop fly, while interference was waived off by 1B Umpire Ron Kulpa in the bottom of the 9th inning of Boston's walk-off victory over Detroit during Game 2 of the American League Championship Series. The terminology "non-fan interference foul" is used because this play does not qualify under the rules book definition of spectator interference. Batter Jarrod Saltalamacchia would eventually hit a walk-off RBI single to win the game for the Red Sox.

Replays suggest no fan interference occurred.

Summary
For spectator interference to exist on this type of a play (fair or foul fly ball near the stands), pursuant to Rule 2.00 (Interference)(d), a spectator must (i) reach out of the stands and over the playing field and (ii) touch either (1) a live ball or (2) a player and hinder an attempt to make a play on said live ball. Video replay of the Fielder play suggests the fans did satisfy criterion (ii) by touching a player and hindering an attempt to make a play on a live ball, but did not satisfy criterion (i) because the spectators did not reach over the playing field, though they may have reached out of the stands. Accordingly, the ruling and result of this play was both technically and functionally proper and correct.

Related: Rule 3.16: Spectator Interference on Batted Ball
Related: ALDS Game 4 (OAK-DET): The Fan Interference Home Run

Long-Form Explanation
As we determined during the Fan Interference Home Run, Rules 2.00 INT(d) and 3.16 are relevant:

Alternate view of the Fielder play.

Rule 2.00 (Interference)(d): "Spectator interference occurs when a spectator reaches out of the stands and over the playing field, or goes on the playing field, and (1) touches a live ball or (2) touches a player and hinders an attempt to make a play on a live ball."

Rule 3.16: "When there is spectator interference with any thrown or batted ball, the ball shall be dead at the moment of interference and the umpire shall impose such penalties as in his opinion will nullify the act...
APPROVED RULING: If spectator interference clearly prevents a fielder from catching a fly ball, the umpire shall declare the batter out."

Rule 3.16 Comment additionally specifies that "No interference shall be allowed when a fielder reaches over a fence, railing, rope or into a stand to catch a ball. He does so at his own risk. However, should a spectator reach out on the playing field side of such fence, railing or rope, and plainly prevent the fielder from catching the ball, then the batsman should be called out for the spectator’s interference."

As the photograph above indicates, the fan(s) who made contact with Fielder did not actually reach "over the playing field" (as in 2.00 INT d) or "out on the playing field side of such fence" (as in 3.16 Comment), making Rule 2.00 (Interference)(d) inapplicable. Because 2.00 INT d does not apply, Rule 3.16 cannot apply (confirmed by Rule 3.16 Comment's phrasing) and the batsman cannot be called out for spectator's interference, as no interference actually occurred. Fielder also appeared to lean back over the short wall, and in doing so, reached "over a fence" at his own risk.

The playing field side of such fence simply means the vertical facing of the padded wall along the playing field. This plane itself is fair game for fans, but any activity on the playing field side of that plane allows for the fan interference call. To put it metaphorically, had this play occurred in left field along the tall wall in the corner, and the fielder unable to make a play on the ball due to the vertical wall, the ball would be ruled foul. Similarly, the fans are themselves empowered by rule to make a "wall" out of their own person, as long as this "wall" is flush with the brick and mortar wall below and does not protrude over the playing field whatsoever.

Bartman did not interfere, either.

The rule, as presently written (and amended for the 2013 season to include the phrase and over the playing field), removes any potential grey area from enforcement of this rule: If the fan does not interfere over the playing field proper—usually over a dirt warning track if in foul territory—then this type of player-fan contact cannot result in an interference call.

We remember the Steve Bartman play, a 10-year anniversary in foul territory down the Wrigley Field foul line in Chicago. LF Umpire Mike Everitt (who is working the 2013 NLCS) ruled no interference back then and he was correct in doing so, as outfielder Alou reached over a fence and, yes, railing too, to attempt to make a play, doing so at his own risk.

As it was back then, tonight's call by 1B Umpire Ron Kulpa was proper and correct.
Video: Saltalamacchia fouls a ball off—barely—are Fielder attempts to catch ball over short wall