There really isn't enough evidence to prove that he committed the crime, so it's (highly) 'improbable' that he'll be convicted.
The story includes a number of absurd 'improbabilities'. [=improbable events or situations]
The team made an 'improbable' comeback.
(..) Dialogue: ..,Default,,,he would be a public defender. Dialogue: ..,Default,,,Well, actually, given his low\Nsocioeconomic status, Dialogue: ..,Default,,,it is highly improbable Dialogue: ..,Default,,,he would have been able\Nto afford law school. Dialogue: ..,Default,,,(Whispering):\NBones. (..)2016 TvShow: Bones Title: The Death in the Defense Season: 11 Episode 11