At the altar, Jamie has his grandfather and brother as groomsmen. But when Eddie walks down the aisle, there are no bridesmaids.
"Here Comes the Bride" is a secular work and as such would not likely be part of a Catholic wedding mass, especially one being officiated by an archbishop.
In a murder investigation, a witness would be formally interviewed by a detective and their statement recorded. What the patrol officer observed would be recorded in their notebook. Any significant change in witness testimony would be discovered well before the witness met with an ADA. If it changed as it was portrayed, the witness would likely be charged with giving a false statement.
Baker has a number of case files for review of the investigative process and acts like she does not know what to do. Since she is a detective, she would be aware of the investigative process.
On their second visit, the detectives question the female suspect after she had refused to answer questions without a lawyer present. Anything she said would be inadmissible.