Answer :

Tails
The main concern would be that California entered as a free state, messing with the balance of slave and free states in the U.S Senate.

The House was free-leaning, as more people lived in the north than the south, but as every state sent only 2 representatives to the U.S Senate, the south was keen on keeping the balance there.
Beae
ill say that the california outlawed slavery. Southern states didn't want California to be admitted to the union as a free state because it would upset the balance of free states to slave states. This was compromised Later in 1850.