Need help legal wise with weed

OK so here's what happened.

So me and my 2 buddies are smoking weed at a old lowes parking lot. 2 cars we got done smoking like 15 minutes ago. Afternoon. They roll up and start asking us questions. The car smelled liked weed ( we hot boxed).

They make us get out of the car. They search all of us FIND NOTHING. Without asking me and before placing me under arrest they SEARCH my fucking car without asking.

They find 1 gram and place me under arrest, They wanted to tow my car and fuck with me saying if i dont snitch my dealer out i'll be fucked. I said I won't snitch so he made me sit in the back of the police car with hand cuffs on hella tight which left marks for around 45 minutes.

Now they give me a court date with under 40 grams of weed on me.

The question is did they legally or illegally search my car?
I was parked with the keys NOT inside the ignition.

Funny part is they only found 1 gram, I had 3 more hidden lol and I smoked it all right after they let us go with our criminal court dates.

I live in washington state. Any help would be appreciated im 18 and dont need this shit on my record.

if im not mistaken in most instances the odor of maurijuana is reasonable cause to search the best thing to do is check your local laws also i believe in most cases that a gram is a misdemeanor and usually only carry a fine and or probation