By simply looking at the car tyres, why did the police officers conclude that the car was on bad mechanical condition, yet the car was fairly new as it was only one year old? ?

The police officers likely concluded that the car was in bad mechanical condition based on the condition of the tyres. If the tyres were worn down, bald, or showing signs of uneven wear, it could indicate that the car had not been properly maintained or that there were issues with the suspension or alignment. Even though the car was only one year old, poor maintenance or driving habits could have caused the tyres to deteriorate quickly. This could be a red flag for the overall condition of the vehicle.

The provided context does not mention anything about the police officers concluding that the car was on bad mechanical condition by looking at the car tyres. So I cannot answer this question from the provided context.