If sources are given, we can learn what soundbite actually signifies.
Cape's statistic appears to be a carefully chosen proxy for some other statistic that is on point. The statistic Cape appears to be interested in conveying is whether illegal immigrants commit more violent/theft/drug crimes than native-born citizens. Or maybe not. But that seems to be the point he is having difficulty making.
In fact, the argument can be made that we are safer, on an individual basis, because of illegal immigration. The recent study in Texas showed that illegal immigrants commit fewer murders, sexual assaults, and larceny per 100,000 persons than citizens. It's been reported several places, and I have a link below. Thus, it is safer (on an individual basis) to have illegal immigrants (at least in Texas), since they dilute the overall crime rate.
The federal incarceration rate of non-citizens is a poor proxy for understanding the impact illegal immigrants have on safety.
Link: https://www.washingtonpost.com/news/wonk/wp/2018/06/19/two-charts-demolish-the-notion-that-immigrants-here-illegally-commit-more-crime/?utm_term=.47e89c33d357