Not trying to preach here but there's a Biblical verse about "Avoiding the appearance of evil."I'm ok if we don't waste money on a crininal trial. Hopefully there is enough evidence to use in immigration court. Send them back. Stamp the passports with "removed for criminal acts". Make them permanently inelgible to ever enter again. Let their home country deal with them if they want.
If the verse is good enough for the Bible it's good enough for deportation.