Richard Sherman should have been flagged for pass interference. This is why he wasn't.

The Seattle Seahawks’ Richard Sherman committed defensive pass interference against Julio Jones on the Atlanta Falcons’ last play Sunday afternoon. The foul was not called, and the result of the play locked up a win against the Falcons.

There’s little denying the foul occurred, with camera angles from the sky showing Sherman’s hand turning Jones into a one-armed receiver. Yet none of the seven officials on the field threw a penalty flag.

This is why.

One key axiom — maybe THE key axiom -- of officiating is that you have to see the call to make the call. For example, you can’t call a touchdown because you saw the pile move into the end zone. A touchdown has to do with only one thing: The location of the ball. If you don’t actually see the ball cross the goal line, you don’t have a touchdown -- you’d better crash into the middle of the field and find the ball in the pile before you call anything.

That’s the issue at hand with this no-call.

Jones was the main key of the back judge on this play. That means the back judge was watching Jones the entire time. So how did he miss the call?

Understand where the seven officials are positioned during a play:

The back judge was positioned perfectly behind the play (he cannot let the play get behind him as he has goal-line responsibilities at this depth). The problem is, looking back at the trio on the receiving end of the ball — Jones, Sherman and Earl Thomas — this is what he saw:

Photo by Otto Greule Jr/Getty Images

He saw the back of Sherman and Jones, Jones’ one hand going up, Sherman looking back at the ball, and the ball hitting the ground.

Despite how good NFL officials are — and they are excellent — they don’t have X-ray vision. The way the players’ bodies were positioned, the back judge had literally zero-point-zero percent chance of seeing the foul. It wasn’t good enough to wonder why Jones was going up with just one hand — the official couldn’t see the foul.

Beyond that, one of the indicators of DPI is players not looking back to the ball. He didn’t have that here, as Sherman was playing the ball.

OK, no worries. On a pass, all officials but the referee should be turning to the receiver once the ball is thrown to help out. If they’ve got a clear look at a big foul, they can call it even if it’s another officials’ key.

The next two most likely officials to see the foul — the field judge and the side judge — were also blocked from the foul by the players’ bodies. Again, no X-ray vision to rely on. In this screen capture you can see the field judge looking at the foul, but he’s seeing the back of Thomas’ head, the back of Sherman’s body and three players making a play on the ball.

The line judge and head linesman could have helped out on that play too. They actually had the best angle to see the foul, as the players’ backs were not to them. Problem is, they were over 35 yards away from the play. The referee and umpire, 50 yards from the play, have no chance to make that call.

You might ask, “How can everyone see that foul except the officials?”

You know who had the best angle of all? The audience with slow-motion instant replay. The camera angles were from the middle of the field and the front of the players, where images show a clear DPI.

“But you can see Falcons coach Dan Quinn screaming about the call! Even he could see it!”

Yep. He and every other coach scream about calls and no-calls on an average of 248 times per game. On this one, he happened to be correct.

After this play Sunday, there is now a growing chorus of calls to allow replay officials in the booth to review pass interference calls. But here’s the kicker: There was no call to review. What these people are really asking for is for replay officials to be able to CREATE foul calls and officiate the game from New York City. That’s a big, ugly can of worms (though it’s a can of worms the CFL has already opened for themselves).

The better solution is one Sherman himself has been advocating for: The addition of an eighth official. The NFL has been tinkering with this over the last two preseasons. The experiment that got a second look this year was the addition of a “middle judge,” who would be positioned about 20 yards into the defensive backfield to help with — wait for it — downfield pass interference.

If Sherman had gotten his way, and that middle judge was standing 10 yards away from the play in the middle of the field, the middle judge would have thrown a flag and the Falcons would have likely won that game.

I would bet my next paycheck that this particular play gets reviewed heavily by NFL head of officials Dean Blandino and the league’s competition committee in the offseason as they decide whether to recommend the addition of an eighth official. I know Falcons fans are now 100 percent for it.

Cyd Zeigler is a high school and college football official in Southern California. He is also the co-founder of SBNation's Outsports.com.