As a judge, here’s the list of items I check when performing the harness and hitch judging.  Note: other judges may or may not check the same things I check. 

* Check cart balance by lifting the shafts.  In a loaded or unloaded cart, there should be only 1 lb of pressure (may be a little heavier depending on the weight of the shafts). Any weight that is heavier than the weight of the shafts indicates that the cart is unbalanced or improperly hitched.

* Check trace tightness.  They should be tight and taut.  If the traces are not fairly taut, it will cause multiple problems.  This is very serious safety issue, and I would consider it to be an unsafe rig. 

• The shafts may sway from side to side or up and down. 
• The pull power is coming the shafts and not the traces.  The dog will NOT be using the correct body parts to pull the cart.  
• The cart may lurch when the dog starts to move.  
• The cart may push forward on the dog until the brakes stop it when the dog stops.
• The shafts might come out of the shaft loops and then the dog will not have a way to steer the cart. Example of one case I’ve seen: A standard poodle was pulling a loaded cart up the hill with loose traces. The cart rolled backwards due to the slack in the traces and the shafts came out of the shaft loops. Click on photo for larger version.

 * Check fit of the neck piece on a siwash.  I check out how snug it is, and I check that the prosternum is at the V.  If you put your fingers right at the inside of the V, you should feel the prosternum bone.  If you do not, the neck piece is either too big or too small.  Too big or too small can pinch a dog’s neck.

*Check for tightness of the cinch (forward) and belly band. It should fit the dog perfectly. Not loose, nor too snug.

*Check that the shaft loops are tight and cannot go over the brakes.