A "convenient scapegoat" is a person or thing that is unfairly blamed for something, often to divert attention away from the real problem or responsible party. Full definition
All cats, and feral cats in particular, have become convenient scapegoats for the loss of many species, especially songbirds. (catsinternational.org)
Scratch a little deeper though, says Mariki, and it becomes clear that the animals are often just convenient scapegoats. (newscientist.com)
Most social hardship is caused by their misguided neoliberal economic policies, but migrants represent convenient scapegoats for low - paid labour and struggling public services. (blog.politics.ox.ac.uk)