Regional Jet 200 ER/LR (CRJ200)
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Communication Breakdown
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
General None Reported / Taken
Human Factors
While on a visual into LAN while acting as Pilot Monitoring I noticed our speed was 250 kts. as we approached the pattern at 250 kts; I advised the Captain who was Pilot Flying that we were approaching within 4 miles of an aircraft at under 2;500 feet AGL  with our speed at 250 kts when it should be 200 kts. He responded they won't know and just kept on going above 250 kts until just before base turn.
CRJ-200 First Officer reported that Captain declined to follow speed restrictions while on initial approach.