Looks like a disease-ridden and well-chewed purple leaf plum.

Whatever its ID, if it were at my new place, it would be replaced, probably during my 2nd year on the property..

Agree with Jean, except it may be a purple leaf sand cherry (Prunus x cistena)

its fall ... the leaves will fall off.. along with whatever is attacking the leaves... nothing to do there ... but clean them up afterwards ... EVERYTHING looks like this in fall ...

these would be great plants for you to learn about pruning ... there is some historically bad pruning ... maybe for the fence install ...

the further one.. you could probably cut to about 3 inches.. and with no insult to the root mass it will be 4 feet tall again by next summer ...

and then in the next few years ... having either succeeded or failed.. then you can get rid of them ... or not ...

they are what we call.. a short lived tree ... in tree years.. that mean about 20 years max.. if you are lucky.. and the garden gods favor it ... getting rid of it.. is not that big a deal ...

see you in the shrub or tree forum.. if you are interested in gardening.. and learning to prune...

ken

ps: the link shows.. what well pruned specimens should look like ... in a variety of forms ....

Here is a link that might be useful: link

But the action against the tree/shrub will be repeated next year, and successive years following
You don't have to keep other people's mistakes.

My sand cherry tree/shrubs attracted lots of japanese beetles and had a bad case of black knot. I worked on them for years and finally removed them.