Regional Jet 900 (CRJ900)
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Communication Breakdown; Situational Awareness
ATC Issue All Types; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification
Human Factors
After given the clearance to descend via the DSNEE 4 RNAV arrival by LA Center; we complied and began the descent. Everything went uneventfully until we were switched to the next controller about the DSNEE fix on the arrival. At that time; she gave us a clearance to descend via to 5;000 feet; which is not a published altitude on the arrival. I repeated back the clearance verbatim. The Pilot Flying and I were a little confused with the clearance. I asked the Pilot Flying 'would you like me to clarify' [and] he said yes'. I then asked ATC for a clarification; she gave me the same clearance. I then told the Pilot Flying we are good to go to 5;000 feet. The Pilot Flying continued the descent to 6;800 feet [which is] below the published altitude on the MCKYE fix. He then stopped his descent and asked me to clarify the clearance again. I asked ATC if she wanted us to comply with all the altitudes restrictions on the arrival; [to] which she replied yes to all restrictions. We then stayed at 6;800 feet [and] proceeded to the next fix and altitude and then to our destination. I believe the root cause of this event is a communication error between the flight crew. I believe we as a flight crew should have cleared up the misunderstanding of the clearance together and come to agreement; before we asked ATC the clarify the clearance.
CRJ-900 First Officer reported miscommunication led to overshooting a crossing restriction while executing a 'descend via' clearance.