Generally leaves and other fall debris should be removed before your herbaceous perennials (ex. tulips) emerge. Since the tulips have emerged, hand raking around them is best but remove all the leaves before they begin to compact.

Whether or not you choose to remove the leaves is very much a personal choice. As they are an excellent organic mulch, they can simply be left in place to continue to decay and breakdown and add nutrients to the soil. Some gardeners prefer to have a tidier appearance to their beds and choose to remove them. Removing them also helps to warm the soil as they act as an insulator - this is where the timing factor comes in.

I'd gently brush the leaves away to see what is beginning to emerge. If many of your perennials are showing signs of life, removing the leaves to allow the soil to warm will continue to spur growth. If weather conditions are still tending towards winter cold, you may wish to wait a bit longer. If you do opt to leave the leaves (LOL!), make sure they do not cover the crowns of emerging plants. That can encourage fungal issues and possibly crown rot.

If you do remove the leaves, add them to your compost pile rather than discarding them - they are an excellent source of organic matter. If you don't have a compost pile, now is great time to start one!

In Minnesota, I wouldn't be removing leaves from perennials yet. I have some bitter memories of may frosts that damaged stuff that I had removed the leaf protection from too early. My endless summer hydrangea had a serious set back last year and so did my Sagae hosta.
I just remove the "excess" leaves ( whatever that means) and add wood chips on top of the rest....they decompose and provide compost.
But not for another week for me....about 10 days to 2 weeks for you
Linda C