Dilemma!

Someone along our road lets their dog roam so that he goes into everyone's gardens, even jumping over quite high walls (leaving the evidence behind).  He has not been neutered and does not have a collar/tag although everyone seems know who he belongs to. Our road is a dead end but vehicles come up and down the road at speed (usually from the dog's owner's house) - the owner's other dog was killed by a car a while ago.  We also join onto a busy road and I know that he wanders down onto that road so it can only be a matter of time before there is another accident.
We have just got a puppy and while our back garden is secure for her, it is not secure to him as he is a large dog and can easily get over the wall.  This means that I can't leave her alone for 5 minutes in the back garden (to put the poop sack in the bin in the front garden) without finding him sniffing around in the neighbour's garden and trying to get into ours.
This has been a gripe for a while (finding other dog's poop on your lawn) but this is the last straw.  I am very tempted to report him to the dog warden as I don't think the owner is being responsible - everyone else with dogs along the road (and there are a lot!) keeps them under control and clears up after them (we all wave our black bags at each other!!).
Just wondering what you think?! Am I being a grinch or should we just make our garden walls higher?! 

why not contact the dog owner first and explain your worries, failing that ask the dog wardens advice -- only go along the formal "reporting" by which I assume "complaining" route after that - if you can sort things amicably, and I hope you do, it saves hassle later. You are however certainly entitled to be very concerned about excreta on your lawn and your pup being at risk of disease, attack or pregnancy and to seek help.
R

If a dog is roaming then it's out of control and the owner is responsible. Speak to the dog warden.  If the Warden collects the dog and it's not chipped then a formal conversation will take place and the owner will be charged to get the dog back and for the chipping

Good luck 

it is also illegal for a dog to be in a public place without an I.D. tag so a word in the dog wardens ear may be needed.