Say you are in the middle lane of a 3 lane, one-way street, approaching a 4 lane, 2 way intersection (2 lanes in each direction).

The left lane is marked as turning lane. The middle lane (yours) has no markings or signs indicating what lanes you can or can't turn into. The far right lane has no markings either.

The intersection you are turning left into has 2 lanes going in that direction.

Going by common sense, if you were to turn left at the intersection from the middle lane, you should be ok if you turn into the right lane.

Yet, when asked, a cop says that unless there are signs explicity saying you can turn left at an interesction, you aren't allow to. Thus, a person in the left lane turning into this interesction would have the right of way going into the right lane, because you (in the centre lane) shouldn't be turning left in the first place.

Does this sound absurd to anyone? If you couldn't turn left at an interesction unless it explicitly says so, you wouldn't be able to turn left at the majority of intersections! Does the cop know what he's talking about?

For anyone from the St Catherines area, this occurs as you get off the Garden City Skyway off Dieppe Road, turning left onto Welland Ave.

I know these are posted under the rules of the road, but none seem to directly apply to the situation (or do they?).

I don't think 6 applies because your lane is not designated as anything.

I don't think 7 applies because only one lane is designated as a left-turn lane.

Left turn, at intersection

(6) Where a driver or operator of a vehicle intends to turn to the left into an intersecting highway, he or she shall, where the highway on which he or she is driving has marked lanes for traffic, approach the intersection within the left-hand lane provided for the use of traffic moving in the direction in which his or her vehicle is proceeding or, where it has no such marked lanes, by keeping immediately to the right of the centre line of the highway and he or she shall make the left turn by entering the intersection to the right of the centre line or its extension and by leaving the intersection in the left-hand lane provided for the use of traffic moving in the direction in which his or her vehicle is proceeding where the lane is marked or, where no such lane is marked, by passing immediately to the right of the centre line of the intersecting highway. R.S.O. 1990, c. H.8, s. 141 (6).

Left turn, where multiple lanes

(7) Despite subsection (6), where more than one lane of a highway has been designated as a left-turn lane, the driver or operator of a vehicle intending to turn to the left into an intersecting highway shall approach the intersection in one of the lanes and leave the intersection in the lane of the intersecting highway that corresponds to the lane from which the turn was commenced. R.S.O. 1990, c. H.8, s. 141 (7).

The officer is correct. Look at subsection (6) again:

Where a driver or operator of a vehicle intends to turn to the left into an intersecting highway, he or she shall, where the highway on which he or she is driving has marked lanes for traffic, approach the intersection within the left-hand lane provided for the use of traffic

As the road is divided into lanes, your only choice is to use the left most lane to turn left. It only says that if you want to turn left, you must use the left most lane. It makes no reference to designation. This means, subsection (6) says that you must always turn out of the left lane, and cannot turn left out of any other lane. Subsection (7) says the only time you can turn left from any lane other than the left-most lane is if there is more than one lane designated for turning left. The intersection you refer to has only one designated left turning lane, so you cannot use any other lane to turn left.

Using the centre lane to turn left would not only be illegal, but if you're waiting to turn left, you're now blocking traffic behind you that's trying to go straight.

Thanks.

For what it's worth, since you're on a one-way street (i.e. there's no oncoming traffic) you wouldn't be blocking traffic for people behind you tryihng to go straight.