Enforcement

[sj_31]

B1 (a) intercepts a pass, or (b) catches A's punt, in his end zone. Prior to running the ball out of the end zone, B1 fumbles the ball out of the end zone and it is recovered/downed by B2 at the B-10. During the fumble, B3 clips A1 at the B-4.

Ruling and rule reference?

[Atlanta Blue]

Safety.  End of the run was in the EZ, foul was in advance of that spot, so enforcement from the end of the run.

10-2-2-d-2-b

[sj]

How about this one.

B1 intercepts a pass in his end zone. Prior to running the ball out of the end zone, B1 fumbles the ball out of the end zone and it goes out of bounds at the B10. During the fumble, B3 clips A1 at the B-4.

[ROAD2D1]

Safety in the passing situation as well

[El Macman]

Safety in the passing situation as well

The pure result of the play is a touchback. The fumble from the end zone out of bounds in the field of play triggers the forward fumble out of bounds rule. So the ball is returned to the spot of the fumble. The spot of the fumble (which is the end of the last run) is in the end zone, and Team A (not B) was responsible for putting the ball there. Thus, touchback. 10-2-2-d-2-a says that the Basic Spot in this case is the B-20. Apply the 3 and 1 principle at the Basic Spot, and the penalty is from the spot of the foul (B-4), 1/2 the distance. B, 1/10, B-2.

[sj]

The pure result of the play is a touchback.....

That gets to the point I wanted to be clear on. So the difference between play (a) cited by sj_31 and the play I give is that the result of the play, without foul, is different. So the ruling in his is a safety while mine is what you said...B 1/10 @ B2. Correct?

These plays are so similar that you would think the rulings would be the same.

[ROAD2D1]

I love this site.... El Macman breaks this down really well and clarifies my mistake. I have also struggled with this question as there was a similar one on the Big Sky test. I stand corrected and appreciate the clarification. 

[clearwall]

I've always been curious about that term's etymology...3 and 1. Can someone explain how that came to be? Sorry if this question sounds 

[Hawkeye]

With respect to basic spot enforcement, fouls may occur in 4 different ways:
1. Team A foul behind the basic spot
2. Team A foul beyond the basic spot
3. Team B foul behind the basic spot,and
4. Team B foul beyond the basic spot.

Three of those scenarios get enforced from the basic spot, namely #2, 3 and 4
and One of them gets enforced from the spot of the foul, namely #1

Therefore, Three and One principal.

For ease of writing I used Team A and B, but really the team A designation above refers to the team in possession when the foul occurs and team B refers to the opponents of the team in possession.

[clearwall]

Thanks. I could never figure out the reason for that term

[Andrew McCarthy]

With respect to basic spot enforcement, fouls may occur in 4 different ways:
1. Team A foul behind the basic spot
2. Team A foul beyond the basic spot
3. Team B foul behind the basic spot,and
4. Team B foul beyond the basic spot.

Three of those scenarios get enforced from the basic spot, namely #2, 3 and 4
and One of them gets enforced from the spot of the foul, namely #1

Therefore, Three and One principal.

For ease of writing I used Team A and B, but really the team A designation above refers to the team in possession when the foul occurs and team B refers to the opponents of the team in possession.

I really wish they would reorder the scenarios. The way it's written now it's the One and Three Principal.

[bossman72]

Thanks. I could never figure out the reason for that term

Likewise, they don't call it "ALL but one" because not ALL fouls use that principle like in NFHS.  NCAA has some fouls where they specify the enforcement spot and don't use 3 and 1. (example - Illegal Touching of a pass by a lineman).

[sj_31]

As noted above, with regards to the All-But-One principle, it is not "Team A" and "Team B" but rather the "Team in possession/offense" and the "Team not in possession/defense"

Because Teams A and B retain their designations throughout a given down, applying the 3-and-1 using those definitions could result in an incorrect enforcement (especially on a test).

I know it's a technicality, but it's important.

(Same goes for the Fed and All-But-One)