Mark's gun incident has finally come to a complete end. Although there will be a blemish in the records, it's just a warning, which is relatively quite good. Jimmy himself had both a warning and a suspension record.
Jimmy asked Mark and Julia to continue reviewing past case files, just like Chris did when he first joined the homicide team, allowing him to understand previous cases and become familiar with the investigation process.
Besides reviewing past case files, Jimmy had another idea—to help them connect with NYPD detectives and assist in investigating some cases over there to accumulate experience.
This was a spontaneous idea from Jimmy because the NYPD has more staff and they handle quite a few cases, most of which are dealt with by them. Actually, the number of homicide cases falling into the hands of the FBI is not many, which means Mark and Julia could have quite a bit of free time in their daily work.